U.S. patent number 7,550,547 [Application Number 11/091,509] was granted by the patent office on 2009-06-23 for curable composition.
This patent grant is currently assigned to Kaneka Corporation. Invention is credited to Hiroshi Ando, Toshihiko Okamoto, Katsuyu Wakabayashi.
United States Patent |
7,550,547 |
Wakabayashi , et
al. |
June 23, 2009 |
Curable composition
Abstract
The present invention provides a curable composition which has a
high recovery ratio, a high creep resistance, a practical
curability and storage stability. The present invention relates to
a curable composition comprising a reactive silicon group
containing organic polymer (A) and a carboxylic acid (B), wherein
the composition comprises (I), as the carboxylic acid (B), a
carboxylic acid (C) in which the carbon adjacent to the carbonyl
group is a quaternary carbon atoms and/or the composition comprises
(II) a metal carboxylate (D) formed between a carboxylic acid in
which the carbon atoms adjacent to the carbonyl group is a
quaternary carbon atoms and a metal atom of 208 or less in atomic
weight.
Inventors: |
Wakabayashi; Katsuyu
(Nishinomiya, JP), Okamoto; Toshihiko (Akashi,
JP), Ando; Hiroshi (Akashi, JP) |
Assignee: |
Kaneka Corporation (Osaka,
JP)
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Family
ID: |
32072480 |
Appl.
No.: |
11/091,509 |
Filed: |
March 29, 2005 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20050171315 A1 |
Aug 4, 2005 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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PCT/JP03/12567 |
Oct 1, 2003 |
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Foreign Application Priority Data
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Oct 2, 2002 [JP] |
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2002-290538 |
Jan 27, 2003 [JP] |
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2003-018065 |
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Current U.S.
Class: |
528/15; 528/14;
528/17; 528/18; 528/19; 528/21; 528/34 |
Current CPC
Class: |
C08K
5/09 (20130101); C09K 3/1018 (20130101); C08K
5/09 (20130101); C08L 83/04 (20130101); C08L
83/04 (20130101) |
Current International
Class: |
C08G
77/08 (20060101) |
Field of
Search: |
;528/34,26,14,15,17,18,19,21 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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52-073998 |
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Jun 1977 |
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JP |
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55-009669 |
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Jan 1980 |
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JP |
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55-9669 |
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Jan 1980 |
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JP |
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63-006003 |
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Jan 1988 |
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JP |
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63-006041 |
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Jan 1988 |
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JP |
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01-038407 |
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Feb 1989 |
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JP |
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03-072527 |
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Mar 1991 |
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JP |
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05-125272 |
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May 1993 |
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JP |
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06-322251 |
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Nov 1994 |
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JP |
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08-231758 |
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Sep 1996 |
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JP |
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11-116686 |
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Apr 1999 |
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JP |
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3-062626 |
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Jul 2000 |
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JP |
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2000-345054 |
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Dec 2000 |
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JP |
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2001-342363 |
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Dec 2001 |
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JP |
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2002-285018 |
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Oct 2002 |
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JP |
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2003-206410 |
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Jul 2003 |
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JP |
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WO 2004/031299 |
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Apr 2004 |
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WO |
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Primary Examiner: Moore; Margaret G
Attorney, Agent or Firm: Sughrue Mion, PLLC
Parent Case Text
This application is a continuation-in-part of International
Application No. PCT/JP2003/012567 filed Oct. 1, 2003 and claims
foreign priority based on Japanese Application No. 2002-290538
filed Oct. 2, 2002 and Japanese Application No. 2003-18065 filed
Jan. 27, 2003, the contents of all of which applications are herein
incorporated by reference.
Claims
The invention claimed is:
1. A curable composition comprising: (1) a reactive silicon
group-containing organic polymer (A) which is one or more polymers
selected from the group consisting of a polyoxyalkylene based
polymer, a saturated hydrocarbon based polymer and a (meth)acrylate
based polymer, and (2) a carboxylic acid (B) which is a carboxylic
acid (C) in which the carbon atom adjacent to the carbonyl group is
a quaternary carbon atom, wherein a metal carboxylate formed
between a carboxylic acid and a metal atom of more than 208 in
atomic weight is not contained.
2. The curable composition according to claim 1, comprising no
metal carboxylate.
3. The curable composition according to claim 1, comprising a
nonorganotin metal carboxylate.
4. The curable composition according to claim 3, in which the metal
carboxylate is a tin carboxylate.
5. The curable composition according to claim 1, in which the
organic polymer (A) has an average molecular weight of 500 to
50,000, and has on average, at the ends of the main chain and/or on
the side chains, one or more silicon-containing groups per molecule
represented by the general formula (1): ##STR00013## wherein
R.sup.1 and R.sup.2 are each independently an alkyl group having 1
to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an
aralkyl group having 7 to 20 carbon atoms or a triorganosiloxy
group represented by (R').sub.3SiO- where each R is independently a
substituted or unsubstituted hydrocarbon group having 1 to 20
carbon atoms); each X is independently a hydroxyl or a hydrolyzable
group; a is any one of 0, 1, 2, and 3, b is any one of 0, 1, and 2,
though both a and b are not zero simultaneously; and m is 0 or an
integer of 1 to 19.
6. The curable composition according to claim 5, in which X is an
alkoxy group.
7. The curable composition according to claim 1, in which the
organic polymer (A) is a polyoxypropylene based polymer.
8. The curable composition according to claim 1, comprising an
amine compound (E).
9. A one-component curable composition comprising the curable
composition according to claim 1.
10. An adhesive comprising the curable composition according to
claim 1.
11. A sealant comprising the curable composition according to claim
1.
12. A curable composition comprising: (1) a reactive silicon
group-containing organic polymer (A) which is one or more polymers
selected from the group consisting of a polyoxyalkylene based
polymer, a saturated hydrocarbon based polymer and a (meth)acrylate
based polymer, (2) a carboxylic acid (B) which is a carboxylic acid
(C) in which the carbon atom adjacent to the carbonyl group is a
quaternary carbon atom, and (3) a nonorganotin metal carboxylate
(D) composed of one or more selected from the group consisting of
tin carboxylates, potassium carboxylates, calcium carboxylates,
titanium carboxylates, vanadium carboxylates, manganese
carboxylates, iron carboxylates, cobalt carboxylates, nickel
carboxylates, zinc carboxylates, zirconium carboxylates and niobium
carboxylates.
13. The curable composition according to claim 12, in which the
metal carboxylate is composed of one or more selected from the
group consisting of tin carboxylates, titanium carboxylates, iron
carboxylates and zirconium carboxylates.
14. The curable composition according to claim 13, in which the
metal carboxylate is a tin carboxylate.
15. The curable composition according to claim 12, in which the
organic polymer (A) has an average molecular weight of 500 to
50,000, and has on average, at the ends of the main chain and/or on
the side chains, one or more silicon-containing groups per molecule
represented by the general formula (1): ##STR00014## wherein
R.sup.1 and R.sup.2 are each independently an alkyl group having 1
to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an
aralkyl group having 7 to 20 carbon atoms or a triorganosiloxy
group represented by (R').sub.3SiO- where each R is independently a
substituted or unsubstituted hydrocarbon group having 1 to 20
carbon atoms); each X is independently a hydroxyl or a hydrolyzable
group; a is any one of 0, 1, 2, and 3, b is any one of 0, 1, and 2,
though both a and b are not zero simultaneously; and m is 0 or an
integer of 1 to 19.
16. The curable composition according to claim 15, in which X is an
alkoxy group.
17. The curable composition according to claim 12, in which the
organic polymer (A) is a polyoxypropylene based polymer.
18. The curable composition according to claim 12, comprising an
amine compound (B).
19. A one-component curable composition comprising the curable
composition according to claim 12.
20. An adhesive comprising the curable composition according to
claim 12.
21. A sealant comprising the curable composition according to claim
12.
22. The curable composition according to claim 12, in which the
nonorganotin metal carboxylate (D) is composed of one or more
selected from the group consisting of tin carboxylates, potassium
carboxylates, calcium carboxylates, titanium carboxylates, vanadium
carboxylates,. manganese carboxylates, iron carboxylates, cobalt
carboxylates, nickel carboxylates and zirconium carboxylates.
23. A curable composition comprising: (1) a reactive silicon
group-containing organic polymer (A) which is one or more polymers
selected from the group consisting of a polyoxyalkylene based
polymer, a saturated hydrocarbon based polymer and a (meth)acrylate
based polymer, (2) a carboxylic acid (B), and (3) a nonorganotin
metal carboxylate (D) composed of one or more selected from the
group consisting of tin carboxylates, potassium carboxylates,
calcium carboxylates, titanium carboxylates, vanadium carboxylates,
manganese carboxylates, iron carboxylates, cobalt carboxylates,
nickel carboxylates and zirconium carboxylates, wherein the carbon
atom adjacent to the carbonyl group of the metal carboxylate (D) is
a quaternary carbon atom.
24. The curable composition according to claim 23, in which the
metal carboxylate is composed of one or more selected from the
group consisting of tin carboxylates, titanium carboxylates, iron
carboxylates and zirconium carboxylates.
25. The curable composition according to claim 24, in which the
metal carboxylate is a tin carboxylate.
26. The curable composition according to claim 23, in which the
organic polymer (A) has an average molecular weight of 500 to
50,000, and has on average, at the ends of the main chain and/or on
the side chains, one or more silicon-containing groups per molecule
represented by the general formula (1): ##STR00015## wherein
R.sup.1and R.sup.2 are each independently an alkyl group having 1
to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an
aralkyl group having 7 to 20 carbon atoms or a triorganosiloxy
group represented by (R').sub.3SiO- where each R is independently a
substituted or unsubstituted hydrocarbon group having 1 to 20
carbon atoms); each X is independently a hydroxyl or a hydrolyzable
group; a is any one of 0, 1, 2, and 3, b is any one of 0, 1, and 2,
though both a and b are not zero simultaneously; and m is 0 or an
integer of 1 to 19.
27. The curable composition according to claim 26, in which X is an
alkoxy group.
28. The curable composition according to claim 23, in which the
organic polymer (A) is a polyoxypropylene based polymer.
29. The curable composition according to claim 23, comprising an
amine compound (E).
30. A one-component curable composition comprising the curable
composition according to claim 23.
31. An adhesive comprising the curable composition according to
claim 23.
32. A sealant comprising the curable composition according to claim
23.
Description
TECHNICAL FIELD
The present invention relates to a curable composition comprising
an organic polymer containing a silicon-containing group which has
a hydroxyl or hydrolyzable group bonded to the silicon atom and
which is crosslinkable by forming siloxane bonds (hereinafter
referred to as a "reactive silicon group").
BACKGROUND ART
It is known that an organic polymer containing at least one
reactive silicon group in the molecule has an interesting property
such that even at room temperature the organic polymer yields a
rubber-like cured substance through cross-linking based on the
formation of a siloxane bond involving the hydrolysis reaction and
the like of the reactive silicon group caused by moisture and the
like.
Among these reactive silicon group-containing polymers,
polyoxyalkylene based polymers and polyisobutylene based polymers,
which are disclosed in Japanese Patent Laid-Open Nos. 52-73998,
5-125272, 3-72527, 63-6003, 63-6041, 1-38407 and 8-231758, and the
like, have already been industrially produced to be widely used in
applications to sealants, adhesives, coating materials and the
like.
When resins for use in adhesives used as adhesives for interior
panels, adhesives for external panels, adhesives for tiling,
adhesives for stone tiling, adhesives for finishing walls and
adhesives for vehicle panels and the like are poor in recovery
properties and creep resistance, the adhesive layers are distorted
with time due to the weights of the adherends and external stress
to displace panels, tiles and stone pieces as the case may be.
Additionally, when adhesives for finishing ceilings and adhesives
for finishing floors are poor in recovery properties and creep
resistance, the adhesive layers are distorted with time to form
irregularities on the ceiling surfaces and floor surfaces as the
case may be. Moreover, adhesives for assembling electric,
electronic and precision instruments are poor in recovery
properties and creep resistance, the adhesive layers are distorted
with time to lead to performance degradation of these instruments
as the case may be. Accordingly, the compositions to be used in
these adhesives are required to be excellent in recovery properties
and creep resistance.
Sealants are generally used for the purpose of imparting water
tightness and air tightness by filling these materials in the
joints and gaps between various members. Accordingly, because the
property to follow over a long period the portions to which these
adhesives are used is extremely important, the physical properties
of the cured substances of these adhesives are required to be high
both in elongation and in strength, and to be excellent both in
recovery properties and in durability.
Particularly, excellent recovery properties and durability are
required for compositions to be used for sealants for working
joints in buildings with large joint variation (cap pieces,
periphery of window glass, periphery of window frame/window sash,
curtain wall, various exterior panels), sealants for direct
glazing, sealants for double glazing, sealants for the SSG
technique and the like.
The curable compositions containing these reactive silicon
group-containing organic polymers are cured by use of silanol
condensation catalysts; usually organotin based catalysts having
carbon-tin bonds such as dibutyltin bis(acetylacetonate) are widely
used. However, there is a drawback such that the use of organotin
catalysts degrades the recovery properties and the creep resistance
of curable compositions.
On the other hand, as described in Japanese Patent Laid-Open No.
55-9669, Japanese Patent No. 3062626, and Japanese Patent Laid-Open
Nos. 6-322251 and 2000-345054, divalent tin carboxylates can also
be used as silanol condensation catalysts. The use of these
divalent tin carboxylates yields cured substances improved in
recovery ratio and creep resistance. The use of divalent tin
carboxylates in combination with carboxylic acids can improve the
curability.
However, even by use of the catalysts using divalent tin
carboxylates described in the above described publications in
combination with carboxylic acids, sometimes no practical
curability has been provided.
On the other hand, when a one-component curable composition is
prepared by use of a divalent tin catalyst, there has been a
problem that the curability is found to be degraded after storage.
Japanese Patent Laid-Open No. 2000-345054 discloses a technique
which does not cause the curing retardation by virtue of using a
non-phthalate based plasticizer even when a divalent tin catalyst
is used.
Additionally, Japanese Patent Laid-Open No. 11-116686 describes a
technique to decrease the stress while a high recovery ratio is
maintained, by adding an acid and an amine each in a content larger
than the equimolecular amount in relation to a tin curing
catalyst.
Additionally, in these years it has been pointed out that organotin
compounds exert heavy load to the environment, and accordingly,
catalysts more free from safety problems are required. Further,
from the viewpoint of the environmental protection, catalyst
systems containing no metals have been required.
Among such catalysts containing no metals, there is a catalytic
system in which a carboxylic acid and an amine compound are
simultaneously used, as described in Japanese Patent Laid-Open No.
11-116686. However, this catalytic system is lower in activity than
the above described metal catalysts, and thus this catalytic system
alone has hardly been able to yield practical curability.
Additionally, Japanese Patent Laid-Open No. 2001-342363 discloses a
catalytic system in which a carboxylic acid having a specific
structure and a bismuth carboxylate having a specific structure are
used simultaneously; however, it has been found that when a curable
composition concerned is used as an adhesive with an adherend
substrate made of anode oxidized aluminum or stainless steel plate,
satisfactory adhesion is not obtained in such a way peeling occurs
at the interface between the substrate and the adhesive.
DISCLOSURE OF THE INVENTION
The present invention is a curable composition containing as a main
component a reactive silicon group-containing organic polymer, and
an object of the present invention is to provide, by use of a
non-organotin catalyst, a curable composition small in curing
variation between before and after storage, and satisfactory in
curability, recovery properties and creep resistance, and another
object of the present invention is to provide, by use of a curing
catalyst in nature having no metal atoms, a curable composition
having a practical curability.
As a result of a diligent investigation to solve such problems, the
present inventors perfected the present invention by discovering
that a curable composition having a practical curability can be
obtained by use of a carboxylic acid having a specific structure or
a carboxylic acid derivative having a specific structure as a
silanol condensation catalyst for the above described polymer,
although these catalysts are non-metal catalysts; and a curable
composition exhibiting a sufficiently practical curability, being
small in curing variation between before and after storage, and
having a satisfactory recovery properties and a satisfactory creep
resistance can be obtained by use of a metal carboxylate, and
further by simultaneous use of a carboxylic acid or a carboxylic
acid derivative, and by constraining the acid radical of the metal
carboxylate to have a specific structure although the catalyst
concerned is a non-organotin catalyst.
More specifically, the present invention relates to a curable
composition comprising a reactive silicon group-containing organic
polymer (A) (hereinafter referred to as "organic polymer (A)") and
a carboxylic acid (B),
(I) wherein the composition comprises, as the carboxylic acid (B),
a carboxylic acid (C) in which the carbon atom adjacent to the
carbonyl group is a quaternary carbon atom (hereinafter referred to
as "carboxylic acid (C)); and/or
(II) wherein the composition comprises a metal carboxylate (D)
formed between a carboxylic acid in which the carbon atom adjacent
to the carbonyl group is a quaternary carbon atom and a metal atom
of 208 or less in atomic weight (hereinafter referred to as "metal
carboxylate (D)").
The curable composition may include no metal carboxylate or may
include a metal carboxylate.
It is preferable that the metal carboxylate includes one or more
metal carboxylates selected from the group consisting of tin
carboxylates, potassium carboxylates, calcium carboxylates,
titanium carboxylates, vanadium carboxylates, manganese
carboxylates, iron carboxylates, cobalt carboxylates, nickel
carboxylates, zinc carboxylates, zirconium carboxylates and niobium
carboxylates.
It is more preferable that the metal carboxylate includes one or
more carboxylates selected from the group consisting of tin
carboxylates, titanium carboxylates, iron carboxylates and
zirconium carboxylates.
It is further preferable that the metal carboxylate is a tin
carboxylate.
It is preferable that the organic polymer (A) has an average
molecular weight of 500 to 50000, and has on average, at the
terminal of the main chain and/or the side chains, one or more
silicon-containing groups per molecule represented by the general
formula (1):
##STR00001## where R.sup.1 and R.sup.2 are each independently an
alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to
20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms or a
triorganosiloxy group represented by (R').sub.3SiO-- (R's are each
independently a substituted or a unsubstituted hydrocarbon group
having 1 to 20 carbon atoms); additionally, each X is independently
a hydroxy or a hydrolyzable group; moreover, a is any one of 0, 1,
2, and 3, b is any one of 0, 1, and 2, and a and b are not to be 0
simultaneously; and m is 0 or an integer of 1 to 19.
It is preferable that X is an alkoxy group.
The organic polymer (A) is preferably composed of one or more
selected from the group consisting of polyoxyalkylene based
polymers, saturated hydrocarbon based polymers and (meth)acrylate
based polymers.
The organic polymer (A) is preferably a polyoxypropylene based
polymer.
The curable composition preferably contains an amine compound
(E).
The present invention relates to a one-component curable
composition composed of the above described curable
composition.
The present invention relates to an adhesive composed of the above
described curable composition.
The present invention relates to a sealant composed of the above
described curable composition.
A content of a metal carboxylate formed between a carboxylic acid
and a metal atom of more than 208 in atomic weight in the curable
composition is preferably less than 0.1 parts by weight in relation
to 100 parts by weight of the organic polymer (A).
BEST MODE FOR CARRYING OUT THE INVENTION
No particular constraint is imposed on the main chain skeleton of
the organic polymer (A) to be used in the present invention, and
polymers having various types of main chain skeletons can be
used.
More specifically, examples of the organic polymer (A) include
polyoxyalkylene based polymers such as polyoxyethylene,
polyoxypropylene, polyoxybutylene, polyoxytetramethylene,
polyoxyethylene-polyoxypropylene copolymer, and
polyoxyprolylene-polyoxybutylene copolymer; hydrocarbon based
polymers such as ethylene-propylene based copolymer,
polyisobutylene, copolymers between isobutylene and isoprene and
the like, polychloroprene, polyisoprene, copolymers between
isoprene or butadiene and acrylonitrile and/or styrene and the
like, polybutadiene, copolymers between isoprene or butadiene and
acrylonitrile, styrene and the like, hydrogenated polyolefin based
polymers obtained by hydrogenation of these polyolefin based
polymers; polyester based polymers obtained by the condensation
between dibasic acids such as adipic acid and glycol, or by the
ring-opening polymerization of lactones; (meth)acrylate based
polymers obtained by radical polymerization of the monomers such as
ethyl (meth)acrylate and butyl (meth)acrylate; vinyl based polymers
obtained by radical polymerization of (meth)acrylate based
monomers, and the monomers such as vinyl acetate, acrylonitrile and
styrene; graft polymers obtained by polymerization of vinyl
monomers in the above described organic polymers; polysulfide based
polymers; polyamide based polymers such as nylon 6 obtained by
ring-opening polymerization of .epsilon.-caprolactam, nylon 6,6
obtained by condensation polymerization between
hexamethylenediamine and adipic acid, nylon 6,10 obtained by
condensation polymerization between hexamethylenediamine and
sebacic acid, nylon 11 obtained by condensation polymerization of
.epsilon.-aminoundecanoic acid, nylon 12 obtained by ring-opening
polymerization of .epsilon.-aminolaurolactam, and copolymerized
nylons containing two or more components of the above described
nylons; polycarbonate based polymers manufactured by condensation
polymerization of, for example, bisphenol A and carbonyl chloride;
and diaryl phthalate based polymers. Among the polymers having the
above described main chain skeletons, polyoxyalkylene based
polymers, saturated hydrocarbon based polymers, polyester based
polymers, (meth)acrylate based polymers, and polycarbonate based
polymers are preferable because these polymers are easily available
and can be easily manufactured.
Moreover, saturated hydrocarbon based polymers such as
polyisobutylene, hydrogenated polyisoprene, hydrogenated
polybutadiene, polyoxyalkylene based polymers and (meth)acrylate
based polymers are particularly preferable because these polymers
are relatively low in glass transition temperature and yield cured
substances excellent in low-temperature resistance.
The reactive silicon group contained in the organic polymer (A) is
a group which has a hydroxy or hydrolyzable group bonded to a
silicon atom, and is capable of cross-linking by forming a siloxane
bond through a reaction accelerated by a silanol condensation
catalyst. As the reactive silicon group, there can be cited a group
represented by the general formula (1):
##STR00002## where R.sup.1 and R.sup.2 are each independently an
alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to
20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms or a
triorganosiloxy group represented by (R').sub.3SiO-- (R's are each
independently a substituted or a unsubstituted hydrocarbon group
having 1 to 20 carbon atoms); additionally, each X is independently
a hydroxy or a hydrolyzable group; moreover, a is any one of 0, 1,
2, and 3, b is any one of 0, 1, and 2, and a and b are not to be 0
simultaneously; and m is 0 or an integer of 1 to 19.
No particular constraint is imposed on the hydrolyzable group, and
the hydrolyzable group has only to be a hydrolyzable group well
known in the art. More specifically, examples of the hydrolyzable
group include a hydrogen atom, a halogen atom, an alkoxy group, an
acyloxy group, a ketoximate group, an amino group, an amide group,
an acid amide group, an aminooxy group, a mercapto group, and an
alkenyloxy group. Among these groups, a hydrogen atom, an alkoxy
group, an acyloxy group, a ketoximate group, an amino group, an
amide group, an aminooxy group, a mercapto group and an alkenyloxy
group are preferable; an alkoxy group is particularly preferable
from the viewpoint that an alkoxy group is moderately hydrolyzable
and easily handlable.
To a silicon atom, 1 to 3 hydrolyzable groups and 1 to 3 hydroxy
groups can be bonded, and (a+m.times.b) falls preferably in the
range from 1 to 5. When 2 or more hydrolyzable groups and 2 or more
hydroxy groups are bonded in a reactive silicon group, the
hydrolyzable groups may be the same or different and this is also
the case for the hydroxy group.
The number of the silicon atoms forming the reactive silicon group
is one or more, and is preferably 20 or less in the case of the
silicon atoms connected by siloxane bonds.
In particular, a reactive silicon group represented by the general
formula (2) is preferable because it is easily available:
##STR00003## where R.sup.2 and X are the same as described above,
and c is an integer of 1 to 3.
Additionally, specific examples of R.sup.1 and R.sup.2 in the above
general formulas (1) and (2) include alkyl groups such as a methyl
group and an ethyl group; cycloalkyl groups such as a cyclohexyl
group; aryl groups such as a phenyl group; aralkyl groups such as a
benzyl group; and a triorqanosiloxy group represented by
(R').sub.3SiO-- in which R' is a methyl group, a phenyl group or
the like. Among these groups, a methyl group is particularly
preferable.
More specific examples of the reactive silicon group include a
trimethoxysilyl group, a triethoxysilyl group, a triisopropoxysilyl
group, a dimethoxymethylsilyl group, a diethoxymethylsilyl group,
and a diisopropoxymethylsilyl group. A trimethoxysilyl group, a
triethoxysilyl group and a dimethoxymetylsilyl group are more
preferable because these groups are high in activity and yield
satisfactory curable compositions, and a trimethoxysilyl group is
particularly preferable. Additionally, from the viewpoint of
storage stability, a dimethoxymethylsilyl group is particularly
preferable. The reactive silicon groups having three hydrolyzable
groups on the silicon atom such as a trimethoxysilyl group, a
triethoxysilyl group and a triisopropoxysilyl group are
particularly preferable from the viewpoint of the recovery
properties, durability and creep resistance of the curable
compositions obtained. Additionally, a triethoxysilyl group is
particularly preferable because the alcohol produced by the
hydrolysis reaction of the reactive silicon group is ethanol and
hence a triethoxysilyl group has a high safety.
The introduction of the reactive silicon group can be carried out
by methods well known in the art. More specifically, examples of
such methods include the following:
(a) With an organic polymer having in the molecule functional
groups such as hydroxy groups, an organic compound having both an
active group exhibiting reactivity to the functional groups and an
unsaturated group is reacted, to yield an unsaturated
group-containing organic polymer. Alternatively, an unsaturated
group-containing organic polymer is obtained by copolymerization of
an epoxy compound having an unsaturated group with an organic
polymer having in the molecule functional groups such as hydroxy
groups. Then, a reactive silicon group-containing hydrosilane is
reacted with the reaction product to be hydrosilylated.
(b) With an unsaturated group-containing organic polymer, obtained
similarly to the method described in (a), a mercapto group- and
reactive silicon group-containing compound is reacted.
(c) With an organic polymer having in the molecule functional
groups such as hydroxy groups, epoxy groups and isocyanate groups,
a compound having a functional group exhibiting reactivity to the
functional groups and a reactive silicon group is reacted.
Among the above methods, a method described in (a) or a method
described in (c) in which a hydroxy group-terminated polymer is
reacted with an isocyanate group- and reactive silicon
group-containing compound is preferable because the method provides
a high conversion rate for a relatively short reaction time.
Additionally, the method described in (a) is particularly
preferable because an organic polymer (A) obtained by the method
described in (a) is lower in viscosity and more satisfactory in
workability than an organic polymer obtained by the method
described in (c), and an organic polymer (A) obtained by the method
described in (b) is strong in odor due to mercaptosilane.
Specific examples of the hydrosilane compound used in the method
described in (a) include halogenated silanes such as
trichlorosilane, methyldichlorosilane, dimethylchlorosilane and
phenyldichlorosilane; alkoxysilanes such as trimethoxysilane,
triethoxysilane, methyldiethoxysilane, methyldimethoxysilane and
phenyldimethoxysilane; acyloxysilanes such as methyldiacetoxysilane
and phenyldiacetoxysilane; and ketoximatesilanes such as
bis(dimethylketoximate)methylsilane and
bis(cyclohexylketoximate)methylsilane; however, the hydrosilane
compound used in the method described in (a) is not limited to
these compounds. Among these examples, halogenated silanes and
alkoxysilanes are preferable; in particular, alkoxysilanes are most
preferable because the obtained curable compositions are moderately
hydrolyzable and easily handlable. Among the alkoxysilanes,
methyldimethoxysilane is particularly preferable because
methyldimethoxysilane is easily available, and the curability,
storage stability, elongation property, and tensile strength of the
cured substance containing the obtained organic polymers are
high.
Among the above described hydrosilanes, hydrosilane compounds
represented by the general formula (3) are preferable because
significant is the improvement effect on the recovery properties,
durability and creep resistance of each of the curable compositions
made of organic polymers obtained from addition reaction of the
hydrosilane compounds concerned: H--SiX.sub.3 (3) where X denotes a
hydroxy group or a hydrolyzable group, and when two or more of Xs
are present, these Xs may be either the same or different. Among
the hydrosilane compounds represented by the general formula (3),
trialkoxysilanes such as trimethoxysilane, triethoxysilane and
triisopropoxysilane are more preferable.
Among the above described trialkoxysilanes, trialkoxysilanes such
as trimethoxysilane having alkoxy groups (methoxy groups) each
having one carbon atom sometimes undergoes rapidly proceeding
disproportionation reaction, which yields fairly highly reactive
compounds such as dimethoxysilane. From the viewpoint of handling
safety, it is preferable to use trialkoxysilanes each containing
alkoxy groups having two or more carbon atoms represented by the
general formula (4): H--Si(OR.sup.3).sub.3 (4) where three R.sup.3
each are independently a monovalent organic group having 2 to 20
carbon atoms. Triethoxysilane is most preferable from the viewpoint
of the availability and handling safety thereof, and from the
viewpoint of the recovery properties, durability and creep
resistance of each of the obtained curable compositions.
Examples of the synthesis method described in (b) include a method
in which a mercapto group- and reactive silicon group-containing
compound is introduced into the sites on the unsaturated bonds of
an organic polymer by means of a radical addition reaction in the
presence of a radical initiator and/or a radical generating source;
however, the synthesis method concerned is not limited to these
methods. Examples of the above described mercapto group- and
reactive silicon group-containing compound include
.gamma.-mercaptopropyltrimethoxysilane,
.gamma.-mercaptopropylmethyldimethoxysilane,
.gamma.-mercaptopropyltriethoxysilane and
.gamma.-mercaptopropylmethyldiethoxysilane; however, the mercapto
group- and reactive silicon group-containing compound is not
limited to these compounds.
Examples of the method, of the methods described in (c), in which a
hydroxy-terminated polymer is reacted with an isocyanate group- and
reactive silicon group-containing compound include a method
disclosed in Japanese Patent Laid-Open No. 3-47825; however, the
method concerned is not limited to these methods. Examples of the
above described isocyanate group- and reactive silicon
group-containing compound include
.gamma.-isocyanatopropyltrimethoxysilane,
.gamma.-isocyanatopropylmethyldimethoxysilane,
.gamma.-isocyanatopropyltriethoxysilane, and
.gamma.-isocyanatopropylmethyldiethoxysilane; however, the compound
concerned is not limited to these compounds.
As described above, silane compounds each having three hydrolyzable
groups bonded to one silicon atom such as trimethoxysilane
sometimes undergo proceeding disproportionation reaction, which
yields fairly highly reactive compounds such as dimethoxysilane.
However, with .gamma.-mercaptopropyltrimethoxysilane and
.gamma.-isocyanatopropyltrimethoxysilane, no such reaction
proceeds. Accordingly, when as the silicon-containing group, there
is used a group having three hydrolyzable groups bonded to a
silicon atom such as a trimethoxysilyl group and the like, it is
preferable to use the synthesis methods described in (b) or
(c).
The organic polymer (A) may be a straight chain or may have
branches, and the number average molecular weight thereof, measured
by GPC relative to polystyrene standard, is preferably 500 to
50,000, and more preferably 1,000 to 30,000. When the number
average molecular weight is less than 500, there is found an
adverse trend involving the elongation property, while when the
number average molecular weight exceeds 50000, there is found an
adverse trend involving the workability because the viscosity
becomes high.
For the purpose of obtaining a rubber-like cured substance having a
high strength, a high elongation property and a low elastic
modulus, it is recommended that the number of the reactive groups
contained in the organic polymer (A) is, on average in one polymer
molecule, at least one, and preferably 1.1 to 5. When the average
number of the reactive groups contained in a molecule is less than
1, the curability becomes insufficient, and hence a satisfactory
rubber elasticity behavior can hardly be exhibited. The reactive
silicon group may be located at the terminals of the organic
polymer molecule chain or on the side chains, or both at the
terminals and on the side chains. In particular, when the reactive
silicon groups are located at the molecular terminals, the
effective network content in the organic polymer component
contained in the finally formed cured substance becomes large, so
that it becomes easier to obtain a rubber-like cured substance
having a high strength, a high elongation property and a low
elastic modulus.
Additionally, in the present invention, for the purpose of
obtaining a cured substance having a high recovery properties, a
high durability and a high creep resistance, there can be used an
organic polymer in which the average number of the reactive silicon
groups contained in a molecule is 1.7 to 5. A cross-linked cured
substance obtained using such an organic polymer through the
silanol condensation involving the reactive silicon groups exhibits
a satisfactory recovery properties, and also exhibits marked
improvement effects of the creep resistance and the durability as
compared to the case where an organic polymer in which the average
number of the reactive silicon groups per molecule is less than
1.7. From the viewpoint of the improvement of the recovery
properties, durability and creep resistance, the average number of
the reactive silicon groups contained in one molecule of the
organic polymer is more preferably 2 to 4, and particularly
preferably 2.3 to 3. When the number of the reactive silicon groups
per molecule is less than 1.7, the improvement effect of recovery
properties, durability and creep resistance of a cured substance of
the present invention is sometimes insufficient, while when the
number of the groups concerned is larger than 5, the elongation of
the obtained cured substance sometimes becomes small.
The above described polyoxyalkylene based polymer is essentially a
polymer having the repeating units represented by the general
formula (5): --R.sup.4--O-- (5) where R.sup.4 is a divalent organic
group which has 1 to 14 carbon atoms and is a straight chain or
branched alkylene group. In the general formula (5), R.sup.4 is
preferably a straight chain or branched alkylene group having 1 to
14 carbon atoms, and more preferably 2 to 4 carbon atoms. Examples
of the repeating units represented by the general formula (5)
include:
##STR00004## The main chain skeleton of the polyoxyalkylene based
polymer may be formed of either only one type of repeating unit or
two or more types of repeating units. In particular, in the case
where the polymer is used for a sealant and the like, it is
preferable that the main chain skeleton is formed of a polymer
containing as the main component a propyleneoxide polymer because a
polymer having such a main chain skeleton is amorphous and
relatively low in viscosity.
Examples of the synthesis method of the polyoxyalkylene based
polymer include a polymerization method based on an alkaline
catalyst such as KOH; a polymerization method based on a transition
metal compound-porphyrin complex catalyst prepared by reacting an
organoaluminum compound with porphyrin, disclosed in Japanese
Patent Laid-Open No. 61-215623; polymerization methods based on
double metal cyanide complex catalysts, disclosed in Japanese
Patent Publication Nos. 46-27250 and 59-15336, and U.S. Pat. Nos.
3,278,457, 3,278,458, 3,278,459, 3,427,256, 3,427,334, 3,427,335
and the like; a polymerization method using a catalyst composed of
a polyphosphazene salt disclosed in Japanese Patent Laid-Open No.
10-273512, and a polymerization method using a catalyst composed of
a phosphazene compound disclosed in Japanese Patent Laid-Open No.
11-060722. However, the method concerned is not limited to these
methods.
The main chain skeleton of the above described polyoxyalkylene
based polymer may include other components such as binding urethane
components as far as such inclusion does not largely impair the
effect of the present invention.
No particular constraint is imposed on the above described binding
urethane component; examples of the binding urethane component can
include the compounds obtained by the reaction between the polyols
having the repeating units represented by the above general formula
(5) and polyisocyanate compounds covering aromatic polyisocyanates
such as toluene (tolylene) diisocyanate, diphenylmethane
diisocyanate and xylene diisocyanate; and aliphatic polyisocyanates
such as isophorone diisocyanate and hexamethylene diisocyanate.
When amide segments (--NR''--CO--) contained in the (thio)urethane
bonds, urea bonds, substituted urea bonds and the like produced in
the main chain skeleton on the basis of the above described
urethane reaction are abundant, R'' being a hydrogen atom or a
substituted or a unsubstituted monovalent hydrocarbon group, the
viscosity of the organic polymer becomes high and forms a
composition poor in workability as the case may be. Accordingly,
the amount of the amide segments occupying the main chain skeleton
of the organic polymer is preferably 3 wt % or less, more
preferably 1 wt % or less, and most preferably substantially
null.
Examples of the manufacturing method of the reactive silicon
group-containing polyoxyalkylene based polymer include the methods
disclosed in Japanese Patent Publication Nos. 45-36319 and
46-12154, Japanese Patent Laid-Open Nos. 50-156599, 54-6096,
55-13767, 55-13468, 57-164123, Japanese Patent Publication No.
3-2450, and U.S. Pat. Nos. 3,632,557, 4,345,053, 4,366,307 and
4,960,844; and the methods manufacturing polyoxyalkylene based
polymers each having a high molecular weight such that the number
average molecular weight is 6,000 or more and a narrow molecular
weight distribution such that the Mw/Mn value is 1.6 or less,
disclosed in Japanese Patent Laid-Open Nos. 61-197631, 61-215622,
61-215623, 61-218632, 3-72527, 3-47825 and 8-231707. However, the
method concerned is not limited to these methods.
The above described reactive silicon group-containing
polyoxyalkylene based polymers may be used either each alone or in
combinations of two or more thereof.
The above described saturated hydrocarbon based polymers are the
polymers which substantially do not contain carbon-carbon
unsaturated bonds other than aromatic rings; the polymers forming
the skeletons of the saturated hydrocarbon based polymers can be
obtained by the methods in which (1) olefin based compounds having
1 to 6 carbon atoms such as ethylene, propylene, 1-butene and
isobutylene are polymerized as main monomers, and (2) diene based
compounds such as butadiene and isoprene are homopolymerized or
copolymerized with the above described olefin based compounds and
then hydrogenation is applied; however, isobutylene based polymers
and hydrogenated polybutadiene based polymers are preferable
because functional groups can be easily introduced into the
terminals of these polymers, the molecular weights of these
polymers can be easily controlled and the number of the terminal
functional groups can be increased; and isobutylene based polymers
are particularly preferable because of the ease of the synthesis
thereof.
The polymers having saturated hydrocarbon based polymers as the
main chain skeleton are characterized in that the polymers each
having such a skeleton are excellent in heat resistance, weather
resistance, durability and moisture blocking property.
The isobutylene based polymers may be formed in such a way that all
the monomer units are solely isobutylene units, or my be copolymers
with monomers other than isobutylene units; however, from the
viewpoint of the rubber property, in each of the polymers
concerned, the content of the units derived from isobutylene is
preferably 50 wt % or more, more preferably 80 wt % or more, and
most preferably 90 to 99 wt %.
As for the synthesis methods of saturated hydrocarbon based
polymers, various types of polymerization methods have hitherto
been reported, particularly among which are many so-called living
polymerization methods developed in these years. It has been known
that the saturated hydrocarbon based polymers, in particular, the
isobutylene based polymers can be easily produced by use of the
inifer polymerization discovered by Kennedy et al. (J. P. Kennedy
et al., J. Polymer Sci., Polymer Chem. Ed., Vol. 15, p. 2843
(1997)) in such a way that polymers having the molecular weights of
the order of 500 to 100,000 can be polymerized with the molecular
weight distribution of 1.5 or less and various types of functional
groups can be introduced into the molecular terminals.
The manufacturing methods of the reactive silicon group-containing
saturated hydrocarbon based polymers are described, for example, in
Japanese Patent Publication Nos. 4-69659 and 7-108928, Japanese
Patent Laid-Open Nos. 63-254149, 64-22904 and 1-197509, Japanese
Patent Nos. 2539445 and 2873395, Japanese Patent Laid-Open No.
7-53882 and the like; however, the methods concerned are not
particularly limited to these methods.
The above described reactive silicon group-containing saturated
hydrocarbon based polymers may be used either each alone or in
combinations of two or more thereof.
No particular constraint is imposed on the (meth)acrylate based
monomers constituting the main chains of the above described
(meth)acrylate based polymers, but various types can be used.
Examples of the monomers concerned include (meth)acrylic acid based
monomers such as (meth)acrylic acid, methyl (meth)acrylate, ethyl
(meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate,
n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl
(meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate,
cyclohexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl
(meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate,
decyl (meth)acrylate, dodecyl (meth)acrylate, phenyl
(meth)acrylate, tolyl (meth)acrylate, benzyl (meth)acrylate,
2-methoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate,
2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate,
stearyl (meth)acrylate, glycidyl (meth)acrylate, 2-aminoethyl
(meth)acrylate, .gamma.-(methacryloyloxypropyl) trimethoxysilane,
.gamma.-(methacryloyloxypropyl)dimethoxymethylsilane, ethylene
oxide adduct of (meth)acrylate, trifluoromethylmethyl
(meth)acrylate, 2-trifluoromethylethyl (meth)acrylate,
2-perfluoroethylethyl (meth)acrylate,
2-perfluoroethyl-2-perfluorobutylethyl (meth)acrylate,
perfluoroethyl (meth)acrylate, trifluoromethyl (meth)acrylate,
bis(perfluoromethly)methyl (meth)acrylate,
2-trifluoromethyl-2-perfluoroethylethyl (meth)acrylate,
2-perfluorohexylethyl (meth)acrylate, 2-perfluorodecylethyl
(meth)acrylate and 2-perfluorohexadecylethyl (meth)acrylate. For
the above described (meth)acrylate based polymers, (meth)acrylate
based monomers can be copolymerized with the following vinyl based
monomers. Examples of the vinyl based monomers concerned include
styrene based monomers such as styrene, vinyltoluene,
.alpha.-methylstyrene, chlorostyrene, and styrenesulfonic acid and
the salts thereof; fluorine containing vinyl monomers such as
perfluoroethylene, perfluoropropylene and fluorinated vinylidene;
silicon containing vinyl based monomers such as
vinyltrimethoxysilane and vinyltriethoxysilane; maleic anhydride,
maleic acid, and monoalkyl esters and dialkyl esters of maleic
acid; fumaric acid, and monoalkyl esters and dialkyl esters of
fumaric acid; maleimide based monomers such as maleimide,
methylmaleimide, ethylmaleimide, propylmaleimide, butylmaleimide,
hexylmaleimide, octylmaleimide, dodecylmaleimide, stearylmaleimide,
phenylmaleimide, cyclohexylmaleimide; nitrile group containing
vinyl based monomers such as acrylonitrile and methacrylonitrile;
amide group containing vinyl based monomers such as acrylamide and
methacrylamide; vinyl esters such as vinyl acetate, vinyl
propionate, vinyl pivalate, vinyl benzoate and vinyl cinnamate;
alkenes such as ethylene and propylene; conjugated dienes such as
butadiene and isoprene; and vinyl chloride, vinylidene chloride,
allyl chloride and allylalcohol. These monomers may be used either
each alone or two or more of these monomers may be copolymerized.
Among these, from the viewpoint of the physical properties of the
products, polymers formed of styrene based monomers and
(meth)acrylic acid based monomers are preferable. More preferable
are the (meth)acryl based polymers formed of acrylate monomers and
methacrylate monomers, and particularly preferable are the acryl
based polymers formed of acrylate monomers. For general
construction applications, the butyl acrylate based monomers are
further preferable because compositions concerned each are required
to have physical properties including a low viscosity, and the
cured substances each are required to have physical properties
including a low modulus, a high elongation property, a weather
resistance and a heat resistance. On the other hand, for
applications to vehicles and the like where oil resistance is
required, copolymers made of ethyl acrylate as the main material
are further preferable. The copolymers made of ethyl acrylate as
the main material are excellent in oil resistance, but slightly
tend to be poor in low-temperature property (low-temperature
resistance); for the purpose of improving the low-temperature
property thereof, part of ethyl acrylate can be replaced with butyl
acrylate. However, with the increase of the ratio of butyl
acrylate, the satisfactory oil resistance comes to be degraded, so
that for the application to the use requiring oil resistance, the
ratio of butyl acrylate is set preferably at 40% or less, and more
preferably at 30% or less. Additionally, it is also preferable to
use 2-methoxyethyl acrylate and 2-ethoxyethyl acrylate which have
side chain alkyl groups containing oxygen atoms introduced for the
purpose of improving the low-temperature property and the like
without degrading the oil resistance; in this connection, it is to
be noted that the introduction of alkoxy groups having an ether
bond in the side chains tends to degrade the heat resistance, so
that the ratio of such an acrylate is preferably 40% or less when
heat resistance is required. It is possible to obtain appropriate
polymers by varying the ratio in consideration of required physical
properties such as oil resistance, heat resistance and
low-temperature property according to the various applications and
the required objectives. Examples of the polymers excellent in the
balance between the physical properties including the oil
resistance, heat resistance, low-temperature property and the like
include a copolymer of ethyl acrylate/butyl acrylate/2-methoxyethyl
acrylate (40 to 50/20 to 30/30 to 20 in ratio by weight), this
copolymer imposing no constraint on the polymers concerned. In the
present invention, these preferable monomers can be copolymerized
with other monomers, and moreover, block copolymerized with other
monomers; in such cases, it is preferable that the preferable
monomers are contained in 40% or more in ratio by weight.
Incidentally, it is to be noted that in the above form of
presentation, for example, "(meth)acrylic acid" means acrylic acid
and/or methacrylic acid.
No particular constraint is imposed on the synthesis methods of the
(meth)acrylate based polymers, and the methods well known in the
art can be applied. However, polymers obtained by the usual free
radical methods using azo based compounds and peroxides as
polymerization initiators have a problem such that the molecular
weight distribution values of the polymers are generally larger
than 2 and the viscosities of the polymers are high. Accordingly,
it is preferable to apply living radical polymerization methods for
the purpose of obtaining (meth)acrylate based polymers being narrow
in molecular weight distribution and low in viscosity, and
moreover, having cross-linking functional groups at the molecular
chain terminals in a high ratio.
Among "the living radical polymerization methods," "the atom
transfer radical polymerization method" in which (meth)acrylate
based monomers are polymerized by use of an organic halogenated
compound or a halogenated sulfonyl compound as an initiator and a
transition metal complex as a catalyst has, in addition to the
features of the above described "living radical polymerization
methods," halogen atoms at the terminals relatively favorable for
the functional group conversion reaction and is large in freedom
for designing the initiator and the catalyst, so that the atom
transfer radical polymerization method is further preferable as a
method for manufacturing (meth)acrylate based polymers having
particular functional groups. Examples of the atom transfer radical
polymerization method include the method reported by Matyjaszewski
et al. in Journal of the American Chemical Society (J. Am. Chem.
Soc.), Vol. 117, p. 5614 (1995).
As a manufacturing method of a reactive silicon group-containing
(meth)acrylate based polymer, for example, Japanese Patent
Publication Nos. 3-14068 and 4-55444, and Japanese Patent Laid-Open
No. 6-211922 and the like disclose manufacturing methods which
apply the free radical polymerization methods using chain transfer
agents. Additionally, Japanese Patent Laid-Open No. 9-272714 and
the like disclose a manufacturing method which applies the atom
transfer radical polymerization method. However, the manufacturing
method concerned is not limited to these methods.
The above described reactive silicon group-containing
(meth)acrylate based polymers may be used either each alone or in
combinations of two or more thereof.
These organic polymers (A) may be used either each alone or in
combinations of two or more thereof. Specifically, there can be
used organic polymers formed by blending two or more polymers
selected from the group consisting of the reactive silicon
group-containing polyoxyalkylene based polymers, the reactive
silicon group-containing saturated hydrocarbon based polymers, and
the reactive silicon group-containing (meth)acrylate based
polymers.
The manufacturing methods of the organic polymers formed by
blending the reactive silicon group-containing polyoxyalkylene
based polymers with the reactive silicon group-containing
(meth)acrylate based polymers are proposed in Japanese Patent
Laid-Open Nos. 59-122541, 63-112642, 6-172631, 11-116763 and the
like. However, the manufacturing method concerned is not limited to
these methods. A preferable specific example is a manufacturing
method in which a reactive silicon group-containing polyoxyalkylene
based polymer is blended with a copolymer formed of two
(meth)acrylate monomer units: one (meth)acrylate monomer unit has
the reactive silicon groups and alkyl groups having 1 to 8 carbon
atoms, and the molecular chain substantially represented by the
following general formula (6):
##STR00005## where R.sup.5 represents a hydrogen atom or a methyl
group, and R.sup.6 represents an alkyl group having 1 to 8 carbon
atoms; and the other (meth)acrylate monomer unit has alkyl groups
having 10 or more carbon atoms represented by the following formula
(7):
##STR00006## where R.sup.5 is the same as above, and R.sup.7
represents an alkyl group having 10 or more carbon atoms.
In the above general formula (6), examples of R.sup.6 include alkyl
groups having 1 to 8 carbon atoms, preferably 1 to 4 carbon atoms
and further preferably 1 to 2 carbon atoms such as a methyl group,
an ethyl group, a propyl group, a n-butyl group, a t-butyl group
and a 2-ethylhexyl group. It is also to be noted that R.sup.6 may
represent either one type or admixtures of two or more types.
In the above general formula (7), examples of R.sup.7 include long
chain alkyl groups having 10 or more carbon atoms, usually 10 to 30
carbon atoms, and preferably 10 to 20 carbon atoms such as a lauryl
group, a tridecyl group, a cetyl group, a stearyl group and a
behenyl group. It is also to be noted that R.sup.7 may represent,
similarly to R.sup.6, either one type or admixtures of two or more
types.
The molecular chains of the above described (meth)acrylate based
copolymers are substantially formed of the monomer units
represented by formulas (6) and (7): "substantially" as referred to
here means that in the copolymer concerned the sum content of the
monomer unit of formula (6) and the monomer unit of formula (7)
exceeds 50 wt %. The sum content of the monomer units of formulas
(6) and (7) is preferably 70 wt % or more.
Additionally, the abundance ratio by weight of the monomer unit of
formula (6) to the monomer unit of formula (7) is preferably 95:5
to 40:60, and further preferably 90:10 to 60:40.
Examples of the monomer units other than the monomer units of
formulas (6) and (7) which may be contained in the above described
copolymer include acrylic acids such as acrylic acid and
methacrylic acid; monomers containing amide groups such as
acrylamide, methacrylamide, N-methylolacrylamide and
N-methylolmethacrylamide, epoxy groups such as glycidylacrylate and
glycidylmethacrylate, amino groups such as
diethylaminoethylacrylate, diethylaminoethylmethacrylate and
aminoethyl vinyl ether; and monomer units derived from
acrylonitrile, styrene, .alpha.-methylstyrene, alkyl vinyl ethers,
vinyl chloride, vinyl acetate, vinyl propionate and ethylene.
The organic polymers formed by blending a reactive silicon
group-containing saturated hydrocarbon based polymer with a
reactive silicon group-containing (meth)acrylate based copolymer
are proposed in Japanese Patent Laid-Open Nos. 1-168764,
2000-186176 and the like. However the organic polymer concerned is
not limited to these organic polymers.
Moreover, for the manufacturing method of the organic polymers
formed by blending the (meth)acrylate based copolymers having the
reactive silicon functional groups, there can be used additional
methods in which (meth)acrylate based monomers are polymerized in
the presence of a reactive silicon group-containing organic
polymer. These methods are disclosed specifically in Japanese
Patent Laid-Open Nos. 59-78223, 59-168014, 60-228516, 60-228517 and
the like. However, the method concerned is not limited to these
methods.
For the carboxylic acid (B) in the present invention, there can be
used a carboxylic acid (C) in which the carbon atom adjacent to the
carbonyl group is a quaternary carbon atom. The carboxylic acid (B)
functions as a so-called silanol condensation catalyst capable of
forming siloxane bonds from the hydroxy groups or hydrolyzable
groups each bonded to a silicon atom contained in the organic
polymer (A) of the present invention. The use of the carboxylic
acid (C) makes it possible to obtain the rapid curability for the
curable compositions.
The carboxylic acid (B) in the present invention is not limited to
carboxylic acids, but includes carboxylic acid derivatives to yield
carboxylic acids through hydrolysis such as carboxylic anhydrides,
esters, amides, nitriles and acyl chlorides. As the carboxylic acid
(B), carboxylic acids are particularly preferable because of the
high catalytic activity thereof.
Similarly, the carboxylic acid (C) is not limited to carboxylic
acids, but includes carboxylic acid derivatives to yield carboxylic
acids through hydrolysis such as carboxylic anhydrides, esters,
amides, nitriles and acyl chlorides.
Usually, as the silanol condensation catalyst, there are used
metallic catalysts including organotin compounds, metal
carboxylates such as tin carboxylates, and alkoxy metals. On the
contrary, the carboxylic acid (C) in the present invention acts as
a non-metallic catalyst essentially containing no metal, is low in
environmental load as compared to metallic catalysts, and hence can
be said to be a catalyst higher in safety.
So far, Japanese Patent Laid-Open No. 5-117519 has disclosed an
example in which as a curing catalyst, there are used
2-ethylhexanoic acid having a tertiary carbon atom adjacent to the
carbonyl group and the like; however, it can hardly be said that
sufficient curability can be obtained. On the contrary, the
carboxylic acid (C) of the present invention having a quaternary
carbon atom adjacent to the carbonyl group exhibits a markedly
higher catalytic activity as compared to the carboxylic acids
having the tertiary or secondary carbon atom concerned. In other
words, the carboxylic acid (C) of the present invention is a curing
catalyst essentially containing no metal, but yields curable
compositions having practical curability.
Additionally, the carboxylic acid (C) of the present invention
yields curable compositions satisfactory in recovery ratio,
durability, creep resistance, residual tack, dust sticking property
and staining property. Moreover, the carboxylic acid (C) of the
present invention yields curable compositions better in adhesion as
comparison to the cases where other carboxylic acids are used.
Examples of the carboxylic acid (C) include chain carboxylic acids
represented by the general formula (8):
##STR00007## where R.sup.8, R.sup.9 and R.sup.10 each are
independently a substituted or unsubstituted monovalent organic
group, and may include carboxyl groups; and cyclic carboxylic acids
having a structure represented by the general formula (9):
##STR00008## where R.sup.11 is a substituted or unsubstituted
monovalent organic group, R.sup.12 is a substituted or
unsubstituted divalent organic group, and R.sup.11 and R.sup.12 may
include carboxyl groups, and having a structure represented by the
general formula (10):
##STR00009## where R.sup.13 is a substituted or unsubstituted
trivalent organic group and may include carboxyl groups.
Specific examples include chain monocarboxylic acids such as
pivalic acid, 2,2-dimethylbutyric acid, 2-ethyl-2-methylbutyric
acid, 2,2-diethylbutyric acid, 2,2-dimethylvaleric acid,
2-ethyl-2-methylvaleric acid, 2,2-diethylvaleric acid,
2,2-dimethylhexanoic acid, 2,2-diethylhexanoic acid,
2,2-dimethyloctanoic acid, 2-ethyl-2,5-dimethylhexanoic acid,
neodecanoic acid, versatic acid, 2,2-dimethyl-3-hydroxypropionic
acid; chain dicarboxylic acids such as dimethylmalonic acid,
ethylmethylmalonic acid, diethylmalonic acid, 2,2-dimethylsuccinic
acid, 2,2-diethylsuccinic acid, 2,2-dimethylglutaric acid; chain
tricarboxylic acids such as 3-methylisocitric acid and
4,4-dimethylaconitic acid; cyclic carboxylic acids such as
1-methylcyclopentane carboxylic acid,
1,2,2-trimethyl-1,3-cyclopentane dicarboxylic acid,
1-methylcyclohexane carboxylic acid,
2-methylbicyclo[2.2.1]-5-heptene-2-carboxylic acid,
2-methyl-7-oxabicyclo[2.2.1]-5-heptene-2-carboxylic acid,
1-adamantane carboxylic acid, bicyclo[2.2.1]heptane-1-carboxylic
acid and bicyclo[2.2.2]octane-1-carboxylic acid; and
polymethacrylic acid. Compounds having such structures are abundant
in natural products, and such compounds can certainly be used.
Particularly, monocarboxylic acids are more preferable because
monocarboxylic acids are satisfactory in the compatibility with the
organic polymer (A); additionally, chain monocarboxylic acids are
more preferable. Additionally, because of easy availability,
pivalic acid, neodecanoic acid, versatic acid, 2,2-dimethyloctanoic
acid, 2-ethyl-2,5-dimethylhexanoic acid and the like are
particularly preferable.
Additionally, when the carboxylic acid (C) is high in melting point
(high in crystallinity), the carboxylic acid (C) becomes hardly
handlable (the workability thereof becomes poor). Accordingly, the
melting point of the carboxylic acid (C) is preferably 65.degree.
C. or less, more preferably -50 to 50.degree. C., and particularly
preferably -40 to 35.degree. C.
The used amount of the carboxylic acid (C) is preferably of the
order of 0.01 to 20 parts by weight, and further preferably of the
order of 0.5 to 10 parts by weight, in relation to 100 parts by
weight of the organic polymer (A). When the blended amount of the
carboxylic acid (C) exceeds the above described ranges, sometimes
the work life becomes too short and the workability is degraded.
Additionally, sometimes the adhesion is degraded. When the blended
amount of the carboxylic acid (C) is less than the above described
ranges, sometimes the curing rate becomes slow to result in
insufficient curability.
In the present invention, in addition to the carboxylic acid (B), a
metal carboxylate may be contained. The metal carboxylate functions
as a so-called silanol condensation catalyst capable of forming
siloxane bonds from the hydroxy groups or hydrolyzable groups each
bonded to a silicon atom contained in the organic polymer (A); as
compared to other silanol condensation catalysts, the metal
carboxylate can make higher the recovery properties, durability and
creep resistance of the obtained cured substance, and can improve
rapid curability and storage stability.
As the metal carboxylate, because of high catalytic activity,
preferable are tin carboxylates, potassium carboxylates, calcium
carboxylates, titanium carboxylates, vanadium carboxylates,
manganese carboxylates, iron carboxylates, cobalt carboxylates,
nickel carboxylates, zinc carboxylates, zirconium carboxylates,
niobium carboxylates, lead carboxylates, barium carboxylates,
hafnium carboxylates and cerium carboxylates. Among these, because
of small adverse effect on the environment, preferable are tin
carboxylates, potassium carboxylates, calcium carboxylates,
titanium carboxylates, vanadium carboxylates, manganese
carboxylates, iron carboxylates, cobalt carboxylates, nickel
carboxylates, zinc carboxylates, zirconium carboxylates and niobium
carboxylates.
Moreover, tin carboxylates, lead carboxylates, titanium
carboxylates, iron carboxylates and zirconium carboxylates are more
preferable because these carboxylates provide rapid curability to
the curable composition. Tin carboxylates are particularly
preferable because tin carboxylates provide excellent rapid
curability, adhesion and recovery ratio of the curable composition,
and divalent tin carboxylates are most preferable.
Additionally, as the carboxylic acids having the acid radicals of
the metal carboxylates, preferably used are compounds containing
hydrocarbon based carboxylic acid radicals having 2 to 40 carbon
atoms inclusive of the carbonyl carbon atom; because of
availability, hydrocarbon based carboxylic acids having 2 to 20
carbon atoms are particularly preferably used.
Specific examples include straight chain saturated fatty acids such
as acetic acid, propionic acid, butyric acid, valeric acid, caproic
acid, enanthic acid, caprylic acid, octanoic acid, 2-ethylhexanoic
acid, octylic acid, pelargonic acid, capric acid, undecanoic acid,
lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid,
palmitic acid, heptadecanoic acid, stearic acid, nonadecanoic acid,
arachic acid, behenic acid, lignoceric acid, cerotic acid, montanic
acid, melissic acid and lacceric acid; monoene unsaturated fatty
acids such as undecylenic acid, linderic acid, tsuzuic acid,
physeteric acid, myristoleic acid, 2-hexadecenoic acid,
6-hexadecenoic acid, 7-hexadecenoic acid, palmitoleic acid,
petroselic acid, oleic acid, elaidic acid, asclepinic acid,
vaccenic acid, gadoleic acid, gondoic acid, cetoleic acid, erucic
acid, brassidic acid, selacholeic acid, ximenic acid, lumequeic
acid, acrylic acid, methacrylic acid, angelic acid, crotonic acid,
isocrotonic acid and 10-undecenoic acid; polyene unsaturated fatty
acids such as linoelaidic acid, linoleic acid,
10,12-octadecadienoic acid, hiragoic acid, .alpha.-eleostearic
acid, .beta.-eleostearic acid, punicic acid, linolenic acid,
8,11,14-eicosatrienoic acid, 7,10,13-docosatrienoic acid,
4,8,11,14-hexadecatetraenoic acid, moroctic acid, stearidonic acid,
arachidonic acid, 8,12,16,19-docosatetraenoic acid,
4,8,12,15,18-eicosapentaenoic acid, clupanodonic acid, nishinic
acid and docosahexaenoic acid; branched fatty acids such as
1-methylbutyric acid, isobutyric acid, 2-ethylbutyric acid,
isovaleric acid, tuberculostearic acid, pivalic acid and
neodecanoic acid; fatty acids having a triple bond such as
propiolic acid, tariric acid, stearolic acid, crepenynic acid,
ximenynic acid and 7-hexadecynoic acid; alicyclic carboxylic acids
such as naphthenic acid, malvalic acid, sterculic acid, hydnocarpic
acid, chaulmoogric acid and gorlic acid; oxygen containing fatty
acids such as acetoacetic acid, ethoxy acetic acid, glyoxylic acid,
glycolic acid, gluconic acid, sabinic acid, 2-hydroxytetradecanoic
acid, ipurolic acid, 2-hydroxyhexadecanoic acid, jalapinolic acid,
juniperic acid, ambrettolic acid, aleuritic acid,
2-hydroxyoctadecanoic acid, 12-hydroxyoctadecanoic acid,
18-hydroxyoctadecanoic acid, 9,10-dihydroxyoctadecanoic acid,
ricinoleic acid, camlolenic acid, licanic acid, pheronic acid and
cerebronic acid; and halogen substituted monocarboxylic acids such
as chloroacetic acid, 2-chloroacrylic acid and chlorobenzoic acid.
Examples of aliphatic dicarboxylic acids include saturated
dicarboxylic acids such as adipic acid, azelaic acid, pimelic acid,
suberic acid, sebacic acid, ethylmalonic acid, glutaric acid,
oxalic acid, malonic acid, succinic acid, oxydiacetic acid; and
unsatureated dicarboxylic acids such as maleic acid, fumaric acid,
acetylenedicarboxylic acid and itaconic acid. Examples of aliphatic
polycarboxylic acids include tricarboxylic acids such as aconitic
acid, citric acid and isocitric acid. Examples of aromatic
carboxylic acids include aromatic monocarboxylic acids such as
benzoic acid, 9-anthracenecarboxylic acid, atrolactic acid, anisic
acid, isopropylbenzoic acid, salicylic acid and toluic acid; and
aromatic polycarboxylic acids such as phthalic acid, isophthalic
acid, terephthalic acid, carboxyphenylacetic acid and pyromellitic
acid. Additional other examples include amino acids such as
alanine, leucine, threonine, aspartic acid, glutamic acid,
arginine, cysteine, methionine, phenylalanine, tryptophane and
histidine.
The carboxylic acid having the acid radical of the above described
metal carboxylate is preferably 2-ethylhexanoic acid, octylic acid,
neodecanoic acid, oleic acid or naphthenic acid, because
particularly these acids are easily available and low in price, and
satisfactorily compatible with the organic polymer (A).
When the melting point of the carboxylic acid having the acid
radical of the above described metal carboxylate is high (the
crystallinity is high), the metal carboxylate having the acid
radical has similarly a high melting point and is hardly handlable
(poor in workability). Accordingly, the melting point of the
carboxylic acid having the acid radical of the above described
metal carboxylate is preferably 65.degree. C. or less, more
preferably -50 to 50.degree. C., and particularly preferably -40 to
35.degree. C.
Additionally, when the number of the carbon atoms in the carboxylic
acid having the acid radical of the above described metal
carboxylate is large (the molecular weight of the carboxylic acid
concerned is large), the metal carboxylate having the acid radical
takes a solid form or a highly viscous liquid form, becoming hardly
handlable (degrading the workability thereof). On the contrary,
when the number of the carbon atoms in the above described
carboxylic acid is small (the molecular weight thereof is small),
sometimes the metal carboxylate having the acid radical contains
such components that are easily evaporated by heating, and the
catalytic activity of the metal carboxylate is degraded.
Particularly, under the conditions that the composition is extended
thinly (a thin layer), sometimes the evaporation due to heating
becomes significant, and the catalytic activity of the metal
carboxylate is largely degraded. Accordingly, for the above
described carboxylic acid, the number of the carbon atoms inclusive
of the carbonyl carbon atom is preferably 2 to 20, more preferably
6 to 17, and particularly preferably 8 to 12.
From the viewpoint of easy handling properties (workability and
viscosity) of the metal carboxylate, the metal carboxylate is
preferably a metal dicarboxylate or a metal monocarboxylate, and
more preferably a metal monocarboxylate.
Additionally, the above described metal carboxylate is preferably a
metal carboxylate in which the carbon atom adjacent to the carbonyl
group is a tertiary carbon atom (tin 2-ethylhexanoate and the like)
or a metal carboxylate in which the carbon atom adjacent to the
carbonyl group is a quaternary carbon atom (tin neodecanoate, tin
pivalate and the like) because of rapid curing rate, and is
particularly preferably a metal carboxylate in which the carbon
atom adjacent to the carbonyl group is a quaternary carbon atom.
The metal carboxylate in which the carbon atom adjacent to the
carbonyl group is a quaternary carbon atom is excellent in the
adhesion of the curable composition as compared to other metal
carboxylates. More specifically, tin neodecanoate, tin versatate,
tin 2,2-dimethyloctanoate and tin 2-ethyl-2,5-dimethylhexanoate are
particularly preferable. The above described metal carboxylates may
be used each alone, and additionally may be used in combinations of
two or more thereof.
Additionally, in the present invention, by containing a metal
carboxylate (D) which is a salt between a carboxylic acid in which
the carbon atom adjacent to the carbonyl group is a quaternary
carbon atom and a metal atom of 208 or less in atomic weight, the
cured substance of the organic polymer (A) can be improved in
recovery properties, durability and creep resistance, and
additionally, water resistant adhesion, adhesion durability under
conditions of high temperatures and high humidities, residual tack,
dust sticking property, staining property, surface weather
resistance, heat resistance, weather resistant adhesion to glass
and adhesion to concrete, even when the carboxylic acid (C) in
which the carbon atom adjacent to the carbonyl group is a
quaternary carbon atom is not contained as the carboxylic acid (B)
in the curable composition. The atomic weight of the metal atom is
preferably 6 to 200, more preferably 39 to 185, and further
preferably 120 or less. When the atomic weight of the metal atom is
larger than 208, no satisfactory adhesion can be obtained.
Examples of the carboxylic acid in which the carbon atom adjacent
to the carbonyl group is a quaternary carbon atom and which forms
the metal carboxylate (D) include chain monocarboxylic acids such
as pivalic acid, 2,2-dimethylbutyric acid, 2-ethyl-2-methylbutyric
acid, 2,2-diethylbutyric acid, 2,2-dimethylvaleric acid,
2-ethyl-2-methylvaleric acid, 2,2-diethylvaleric acid,
2,2-dimethylhexanoic acid, 2,2-diethylhexanoic acid,
2,2-dimethyloctanoic acid, 2-ethyl-2,5-dimethylhexanoic acid,
neodecanoic acid, versatic acid, 2,2-dimethyl-3-hydroxypropionic
acid; chain dicarboxylic acids such as dimetylmalonic acid,
ethylmethylmalonic acid, diethylmalonic acid, 2,2-dimethylsuccinic
acid, 2,2-diethylsuccinic acid and 2,2-dimethylglutaric acid; chain
tricarboxylic acids such as 3-methylisocitric acid and
4,4-dimethylaconitic acid; cyclic carboxylic acids such as
1-methylcyclopentane carboxylic acid,
1,2,2-trimethyl-1,3-cyclopentane dicarboxylic acid,
1-methylcyclohexane carboxylic acid,
2-methylbicyclo[2.2.1]-5-heptene-2-carboxylic acid,
2-methyl-7-oxabicyclo[2.2.1]-5-heptene-2-carboxylic acid,
1-adamantane carboxylic acid, bicyclo[2.2.1]heptane-1-carboxylic
acid and bicyclo[2.2.2]octane-1-carboxylic acid; and
polymethacrylic acid.
Examples of the salt between a carboxylic acid in which the carbon
atom adjacent to the carbonyl group is a quaternary carbon atom and
a metal atom of 208 or less in atomic weight include tin
carboxylates, lead carboxylates, potassium carboxylates, calcium
carboxylates, barium carboxylates, titanium carboxylates, zirconium
carboxylates, hafnium carboxylates, vanadium carboxylates,
manganese carboxylates, iron carboxylates, cobalt carboxylates,
nickel carboxylates, cerium carboxylates, zinc carboxylates and
niobium carboxylates.
As the metal carboxylate (D), tin neodecanoate, tin versatate, tin
2,2-dimethyloctanoate and tin 2-ethyl-2,5-dimethylhexanoate are
particularly preferable because of the excellent adhesion of the
curable composition.
The used amount of the metal carboxylate (D) is preferably of the
order of 0.01 to 20 parts by weight, and further preferably of the
order of 0.5 to 10 parts by weight, in relation to 100 parts by
weight of the organic polymer (A). When the blended amount of the
metal carboxylate (D) is less than the above described ranges,
sometimes the curing rate becomes slow, and the curing reaction
hardly proceeds to a sufficient extent. On the other hand, when the
blended amount of the metal carboxylate (D) exceeds the above
described ranges, sometimes the work life becomes too short and the
workability is degraded, and additionally sometimes the storage
stability tends to be degraded.
Additionally, from the viewpoint of load to the environment, it is
preferably that a content of a metal carboxylate (such as bismuth
neodecanoate) formed between a carboxylic acid and a metal atom of
more than 208 in atomic weight in the curable composition of the
present invention is less than 0.1 parts by weight in relation to
100 parts by weight of the organic polymer (A). More preferably,
the metal carboxylate formed between a carboxylic acid and a metal
atom of more than 208 in atomic weight is not contained
substantially. Moreover, bismuth carboxylate such as bismuth
2-ethylhexanoate and bismuth neodecanoate can be effective for the
curing catalyst of the organic polymer in the present invention.
However, it tends to provide a poor adhesion.
The carboxylic acid (B) of the present invention has an effect to
improve the curing activity of the curable composition of the
present invention. Additionally, when the metal carboxylate (D) of
the present invention is used as a curing catalyst, sometimes the
curability is found to be degraded after storage; however, the
curing degradation after storage can be suppressed by adding the
carboxylic acid (B).
The carboxylic acid (B) includes not only carboxylic acids but
carboxylic acid derivatives. Here, the carboxylic acid derivatives
means those compounds which yield carboxylic acids through
hydrolysis such as carboxylic anhydrides, esters, acyl chlorides,
nitrites and amides, and the various derivatives of the above
described carboxylic acids can be used.
As the carboxylic acid (B), carboxylic acids are particularly
preferable from the viewpoint of the high improvement effect of the
curing activity thereof.
Examples of the carboxylic acid (B) can include compounds similar
to the various carboxylic acids having the acid radicals of the
above described metal carboxylates.
Similarly to the carboxylic acids having the acid radicals of the
above described metal carboxylates, as for the above described
carboxylic acid (B), the number of the carbon atoms inclusive of
carbon atom of the carbonyl group is preferably 2 to 20, more
preferably 6 to 17, and particularly preferably 8 to 12.
Additionally, from the viewpoint of the easy handling properties
(workability and viscosity) of the carboxylic acid, the carboxylic
acid is preferably a dicarboxylic acid or a monocarboxylic acid,
and more preferably a monocarboxylic acid. Moreover, the above
described carboxylic acid is preferably a carboxylic acid in which
the carbon atom adjacent to the carbonyl group is a tertiary carbon
atom (2-ethylhexanoic acid and the like) or a carboxylic acid in
which the carbon atom adjacent to the carbonyl group is a
quaternary carbon atom (neodecanoic acid, pivalic acid and the
like) because of rapid curing rate, and is particularly preferably
a carboxylic acid in which the carbon atom adjacent to the carbonyl
group is a quaternary carbon atom.
From the viewpoint of availability, curability and workability, as
the carboxylic acid (B), 2-ethylhexanoic acid, neodecanoic acid,
versatic acid, 2,2-dimethyloctanoic acid and
2-ethyl-2,5-dimethylhexanoic acid are particularly preferable.
The use of the carboxylic acid (B) is effective for the recovery
properties, durability and creep resistance, and additionally,
water resistant adhesion, adhesion durability under conditions of
high temperatures and high humidities, residual tack, dust sticking
property, staining property, surface weather resistance, heat
resistance, weather resistant adhesion to glass and adhesion to
concrete and the like of the cured substance of the organic polymer
(A).
The used amount of the carboxylic acid (B) is preferably of the
order of 0.01 to 20 parts by weight, and further preferably of the
order of 0.5 to 10 parts by weight, in relation to 100 parts by
weight of the organic polymer (A). When the blended amount of the
carboxylic acid (B) is less than the above described ranges,
sometimes the curing rate becomes slow, and the catalytic activity
is found to be degraded after storage. On the other hand, when the
blended amount of the metal carboxylate (D) exceeds the above
described ranges, sometimes the work life becomes too short and the
workability is degraded. Additionally, when the molar quantity of
the carboxylic acid (B) exceeds the molar quantity of the metal
carboxylate (D), sometimes the adhesion is degraded, and hence it
is preferable that the used molar quantity of the carboxylic acid
(B) is less than the used molar quantity of the metal carboxylate
(D).
Additionally, the above described carboxylic acids (B) can be used
each alone, and additionally in combinations of two or more
thereof.
It is to be noted that the curable composition of the present
invention have only to contain the carboxylic acid (B) and the
metal carboxylate (D), but according to need, the carboxylic acid
(C) in which the carbon atom adjacent to the carbonyl group is a
quaternary carbon atom may be used as the carboxylic acid (B).
As described above, examples of the carboxylic acid (C) include
chain carboxylic acids represented by the general formula (8):
##STR00010## where R.sup.8, R.sup.9 and R.sup.10 each are
independently a substituted or unsubstituted monovalent organic
group, and may include carboxyl groups; and cyclic carboxylic acids
including a structure represented by the general formula (9):
##STR00011## where R.sup.11 is a substituted or unsubstituted
monovalent organic group, R.sup.12 is a substituted or
unsubstituted divalent organic group, and R.sup.11 and R.sup.12 may
include carboxyl groups, and including a structure represented by
the general formula (10):
##STR00012## where R.sup.13 is a substituted or unsubstituted
trivalent organic group and may include carboxyl groups.
The number of the carbon atoms in such a carboxylic acid is
preferably 5 to 20, more preferably 6 to 18, and particularly
preferably 8 to 12. When the number of the carbon atoms exceeds
these ranges, the carboxylic acid tends to take a solid form and to
be hardly compatible with the organic polymer (A), and no activity
tends to be obtained. On the other hand, when the number of the
carbon atoms is small, the volatility tends to be increased and the
odor tends to be increased. In view of the availability, curability
and workability, as the carboxylic acid (C), most preferable are
neodecanoic acid, versatic acid, 2,2-dimethyloctanoic acid and
2-ethyl-2,5-dimethylhexanoic acid.
Because a more rapid curability tends to be obtained, it is
preferable to use not only the metal carboxylate (D) but the
carboxylic acid (C) in which the carbon atom adjacent to the
carbonyl carbon atom is a quaternary carbon atom as the carboxylic
acid (B); moreover, it is particularly preferable that the acid
radical of the metal carboxylate (D) and the acid radical of the
carboxylic acid (C) are the same in structure.
When an appropriate curability cannot be obtained only with the
metal carboxylate (D) and the carboxylic acid (B) or the carboxylic
acid (C) due to low activity thereof, the amine compound (E) can be
added as a promoter.
Specific examples of the amine compound (E) include aliphatic
primary amines such as methylamine, ethylamine, propylamine,
isopropylamine, butylamine, amylamine, hexylamine, octylamine,
2-ethylhexylamine, nonylamine, decylamine, laurylamine,
pentadecylamine, cetylamine, stearylamine and cyclohexylamine;
aliphatic secondary amines such as dimethylamine, diethylamine,
dipropylamine, diisopropylamine, dibutylamine, diamylamine,
dihexylamine, dioctylamine, bis(2-ethylhexyl)amine, didecylamine,
dilaurylamine, dicetylamine, distearylamine, methylstearylamine,
ethylstearylamine and butylstearylamine; aliphatic tertiary amines
such as triamylamine, trihexylamine and trioctylamine; aliphatic
unsaturated amines such as triallylamine and oleylamine; aromatic
amines such as laurylaniline, stearylaniline and triphenylamine;
and other amines such as monoethanolamine, diethanolamine,
triethanolamine, 3-hydroxypropylamine, diethylenetriamine,
triethylenetetramine, benzylamine, 3-methoxypropylamine,
3-lauryloxypropylamine, 3-dimethylaminopropylamine,
3-diethylaminopropylamine, xylylenediamine, ethylenediamine,
hexamethylenediamine, triethylenediamine, guanidine,
diphenylguanidine, 2,4,6-tris(dimethylaminomethyl)phenol,
morpholine, N-methylmorpholine, 2-ethyl-4-methylimidazole,
1,8-diazabicyclo(5,4,0)undecene-7 (DBU) and
1,5-diazabicyclo(4,3,0)nonene-5 (DBN). However, the amine (E) is
not limited to these examples.
The auxiliary catalytic activities of these amine compounds (E) are
different from each other, depending on the structures and the
compatibilities thereof with the organic polymer (A), and
accordingly, it is preferable that appropriate compounds are
selected as the amine compounds (E) in conformity with the type of
the organic polymer (A) to be used. When a polyoxyalkylene based
polymer, for example, is used as the organic polymer (A), primary
amines such as octylamine and laurylamine are preferable because
these amines are high in auxiliary catalytic activity;
additionally, preferable are the amine compounds which each have a
hydrocarbon group having at least one hetero atom. Examples of the
hetero atom as referred to here include N, O and S atoms, but the
hetero atom is not limited to these examples. Examples of such
amine compounds (E) include the amines described above under the
category of other amines. Among such amines, more preferable are
the amine compounds each having a hydrocarbon group having a hetero
atom at the carbon atom of at least one position of positions 2 to
4. Examples of such amine compounds (E) include ethylenediamine,
ethanolamine, dimethylaminoethylamine, diethylaminoethylamine,
3-hydroxypropylamine, diethylenetriamine, 3-methoxypropylamine,
3-lauryloxypropylamine, N-methyl-1,3-propanediamine,
3-dimethylaminopropylamine, 3-diethylaminopropylamine,
3-(1-piperazinyl)propylamine and 3-morpholinopropylamine. Among
these amine compounds, 3-diethylaminopropylamine and
3-morpholinopropylamine are more preferable because these two
compounds are high in auxiliary catalytic activity.
3-diethylaminopropylamine is particularly preferable because this
compound leads to curable compositions satisfactory in adhesion,
workability and storage stability. Additionally, when an
isobutylene based polymer is used as the organic polymer (A),
relatively long chain aliphatic secondary amines such as
dioctylamine and distearylamine and aliphatic secondary amines such
as dicyclohexylamine are preferable because of the high auxiliary
catalytic activity of each of these amines.
The blended amount of the amine compound (E) is preferably of the
order of 0.01 to 20 parts by weight and more preferably 0.1 to 5
parts by weight in relation to 100 parts by weight of the organic
polymer (A). When the blended amount of the amine compound (E) is
less than 0.01 part by weight, sometimes the curing rate becomes
slow, and the curing reaction hardly proceeds to a sufficient
extent. On the other hand, when the blended amount of the amine
compound (E) exceeds 20 parts by weight, sometimes the pot life
tends to become too short and the workability is degraded;
additionally sometimes the curing rate becomes slow.
To the curable composition of the present invention, there can be
added a compound (F) (hereinafter referred to as "compound (F)")
which contains within the molecule the reactive silicon group and
other reactive groups. As the reactive silicon group as referred to
here, there can be cited a group which can be described similarly
to the reactive silicon group possessed by the organic polymer (A).
Examples of the other reactive groups include amino groups, epoxy
groups, mercapto groups, vinyl groups, (meth)acryloyl groups,
alkoxy groups, carboxyl groups, isocyanate groups, isocyanurate,
all these groups being either substituted or unsubstituted groups,
and halogens; however, the other reactive groups are not limited to
these groups. A compound which contains within the molecule the
reactive silicon group and other reactive groups means a so-called
silane coupling agent, which acts as an agent providing adhesion.
Specific examples of the silane coupling agent include isocyanate
group-containing silanes such as
.gamma.-isocyanatepropyltrimethoxysilane,
.gamma.-isocyanatepropyltriethoxysilane,
.gamma.-isocyanatepropylmethyldiethoxysilane and
.gamma.-isocyanatepropyl methyldimethoxysilane; amino
group-containing silanes such as
.gamma.-aminopropyltrimethoxysilane,
.gamma.-aminopropyltriethoxysilane,
.gamma.-aminopropyltriisopropoxysilane,
.gamma.-aminopropylmethyldimethoxysilane,
.gamma.-aminopropylmethyldiethoxysilane,
.gamma.-(2-aminoethyl)aminopropyltrimethoxysilane,
.gamma.-(2-aminoethyl)aminopropylmethyldimethoxysilane,
.gamma.-(2-aminoethyl)aminopropyltriethoxysilane,
.gamma.-(2-aminoethyl)aminopropylmethyldiethoxysilane,
.gamma.-(2-aminoethyl)aminopropyltriisopropoxysilane,
.gamma.-(2-(2-aminoethyl)aminoethyl)aminopropyltrimethoxysilane,
.gamma.-(6-aminohexyl)aminopropyltrimethoxysilane,
3-(N-ethylamino)-2-methylpropyltrimethoxysilane,
.gamma.-ureidopropyltrimethoxysilane,
.gamma.-ureidopropyltriethoxysilane,
N-phenyl-.gamma.-aminopropyltrimethoxysilane,
N-benzyl-.gamma.-aminopropyltrimethoxysilane, and
N-vinylbenzyl-.gamma.-aminopropyltriethoxysilane; mercapto
group-containing silanes such as
.gamma.-mercaptopropyltrimethoxysilane,
.gamma.-mercaptopropyltriethoxysilane,
.gamma.-mercaptopropylmethyldimethoxysilane and
.gamma.-mercaptopropylmethyldiethoxysilane; epoxy group-containing
silanes such as .gamma.-glycidoxypropyltrimethoxysilane,
.gamma.-glycidoxypropyltriethoxysilane,
.gamma.-glycidoxypropylmethyldimethoxysilane,
.beta.-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and
.beta.-(3,4-epoxycyclohexyl)ethyltriethoxysilane; carboxysilanes
such as .beta.-carboxyethyltriethoxysilane,
.beta.-carboxyethylphenylbis(2-methoxyethoxy)silane and
N-.beta.-(carboxymethyl)aminoethyl-.gamma.-aminopropyltrimethoxysilane;
vinyl-type unsaturated group-containing silanes such as
vinyltrimethoxysilane, vinyltriethoxysilane,
.gamma.-methacryloyloxypropylmethyldimethoxysilane and
.gamma.-acryloyloxypropylmethyltriethoxysilane; halogen-containing
silanes such as .gamma.-chloropropyltrimethoxysilane; and
isocyanurate silanes such as tris(trimethoxysilyl)isocyanurate.
Additionally, the following derivatives obtained by modifying these
compounds can be used as silane coupling agents: amino-modified
silylpolymer, silylated aminopolymer, unsaturated aminosilane
complex, phenylamino-long chain alkylsilane, aminosilylated
silicone and silylated polyester. Additionally, the reaction
products of the above described silane coupling agents can be used
as the compound (F). Additionally, the compounds (F) may be used
either each alone or in admixtures of two or more thereof.
The compound (F) used in the present invention is usually used
within a range from 0.01 to 20 parts by weight in relation to 100
parts by weight of the organic polymer (A). Particularly, it is
preferable to use the compound (F) within a range from 0.5 to 10
parts by weight.
The effect of the compound (F) added to the curable composition of
the present invention is such that the compound (F) exhibits marked
adhesion improvement effect under either non-primer conditions or
primer-treatment conditions when the compound (F) is applied to
various types of adherends, namely, inorganic substrates made of
glass, aluminum, stainless steel, zinc, copper and mortar and
organic substrates made of polyvinyl chloride, acrylic resin,
polyester, polyethylene, polypropylene and polycarbonate. When the
compound (F) is applied under non-primer conditions, improvement
effect of adhesion to various adherends is particularly
remarkable.
No particular constraint is imposed on the adhesion-imparting
agents other than the above described silane coupling agents, and
specific examples of such adhesion-imparting agents include epoxy
resin, phenolic resin, sulfur, alkyl titanates and aromatic
polyisocyanates. The adhesion-imparting agents may be used either
each alone or in admixtures of two or more thereof. Addition of
these adhesion-imparting agents can improve the adhesion to
adherends.
As the curing catalyst, metal carboxylates are used, and other
curing catalysts can be simultaneously used to an extent not to
degrade the effect of the present invention. Examples of the curing
catalyst include titanium compounds such as tetrabutyl titanate,
tetrapropyl titanate, tetrakis(acetylacetonato)titanium and
bis(acetylacetonato)diisopropoxy titanium; tetravalent organotin
compounds such as dibutyltin dilaurate, dibutyltin maleate,
dibutyltin phthalate, dibutyltin dioctanoate, dibutyltin
bis(2-ethylhexanoate), dibutyltin bis(methylmaleate), dibutyltin
bis(ethylmaleate), dibutyltin bis(butylmaleate), dibutyltin
bis(octylmaleate), dibutyltin bis(tridecylmaleate), dibutyltin
bis(benzylmaleate), dibutyltin diacetate, dioctyltin
bis(ethylmaleate), dioctyltin bis(octylmaleate), dibutyltin
dimethoxide, dibutyltin bis(nonylphenoxide), dibutenyltin oxide,
dibutyltin bis(acetylacetonate), dibutyltin
bis(ethylacetoacetonate), a reaction product of dibutyltin oxide
and a silicate compound, and a reaction product of dibutyltin oxide
and a phthalic acid ester; organoaluminum compounds such as
aluminum tris(acetylacetonate), aluminum tris(ethylacetoacetate)
and diisopropoxyaluminum ethyl acetoacetate; and zirconium
compounds such as zirconium tetrakis(acetylacetonate). Simultaneous
use of these curing catalysts increases the catalytic activity, and
improves the deep-part curability, thin-layer curability, adhesion
and the like. However, an organotin compound, according to the used
amount thereof, degrades the recovery properties, durability and
creep resistance of the cured substance derived from the obtained
curable composition.
For the curable composition of the present invention, silicate can
be used. The silicate acts as a cross-linking agent, and has
functions to improve the recovery properties, durability and creep
resistance of the organic polymer (A) of the present invention.
Moreover, the silicate has effects to improve the adhesion, water
resistant adhesion and adhesion durability under conditions of high
temperatures and high humidities. As the silicate,
tetraalkoxysilane or the partially hydrolyzed condensates thereof
can be used. When the silicate is used, the used amount thereof is
0.1 to 20 parts by weight, and preferably 0.5 to 10 parts by weight
in relation to 100 parts by weight of the organic polymer (A).
Specific examples of the silicate include tetraalkoxysilanes
(tetraalkylsilicates) such as tetramethoxysilane,
tetraethoxysilane, ethoxytrimethoxysilane, dimethoxydiethoxysilane,
methoxytriethoxysilane, tetra-n-propoxysilane,
tetra-i-propoxysilane, tetra-n-butoxysilane, tetra-i-butoxysilane
and tetra-t-butoxysilane, and the partially hydrolyzed condensates
of these silanes.
The partially hydrolyzed condensates of the tetraalkoxysilanes are
more preferable because these condensates are lager in the
improvement effect of the recovery properties, durability and creep
resistance of the present invention than the
tetraalkoxysilanes.
Examples of the above described partially hydrolyzed condensate of
a tetraalkoxysilane include a condensate obtained by the usual way
in which water is added to a tetraalkoxysilane to partially
hydrolyze the tetraalkoxysilane and form the condensate.
Additionally, partially hydrolyzed condensates of organosilicate
compounds are commercially available. Examples of such condensates
include Methyl silicate 51 and Ethyl silicate 40 (both manufactured
by Colcoat Co., Ltd.).
Filler can be added to the composition of the present invention.
Examples of the fillers include reinforcing fillers such as fumed
silica, precipitated silica, crystalline silica, fused silica,
dolomite, anhydrous silicic acid, hydrous silicic acid and carbon
black; fillers such as ground calcium carbonate, precipitated
calcium carbonate, magnesium carbonate, diatomite, sintered clay,
clay, talc, titanium oxide, bentonite, organic bentonite, ferric
oxide, aluminum fine powder, flint powder, zinc oxide, active zinc
white, shirasu balloon, glass microballoon, organic microballoons
of phenolic resin and vinylidene chloride resin, and resin powders
such as PVC powder and PMMA powder; and fibrous fillers such as
asbestos, glass fiber and glass filament. When a filler is used,
the used amount thereof is 1 to 250 parts by weight, and preferably
10 to 200 parts by weight in relation to 100 parts by weight of the
organic polymer (A).
When it is desired to obtain a cured substance high in strength by
use of these fillers, preferable is a filler mainly selected from
fumed silica, precipitated silica, crystalline silica, fused
silica, dolomite, anhydrous silicic acid, hydrous silicic acid,
carbon black, surface treated fine calcium carbonate, sintered
clay, clay and active zinc white; a desirable effect is obtained
when such a filler is used within a range from 1 to 200 parts by
weight in relation to 100 parts by weight of the organic polymer
(A). Additionally, when it is desired to obtain a cured substance
low in tensile strength and large in elongation at break, a
desirable effect is obtained by use of a filler mainly selected
from titanium oxide, calcium carbonate such as ground calcium
carbonate, magnesium carbonate, talc, ferric oxide, zinc oxide and
shirasu balloon within a range from 5 to 200 parts by weight in
relation to 100 parts by weight of the organic polymer (A). It is
to be noted that in general, the calcium carbonate exhibits, with
increasing specific surface area value thereof, an increasing
improvement effect of the tensile strength at break, elongation at
break and adhesion of the cured substance. Needless to say, these
fillers may be used either each alone or in admixtures of two or
more thereof. When calcium carbonate is used, it is desirable to
use surface treated fine calcium carbonate in combination with
calcium carbonate larger in particle size such as ground calcium
carbonate. The particle size of surface treated fine calcium
carbonate is preferably 0.5 .mu.m or less, and the surface
treatment is preferably carried out by treating with a fatty acid
or a fatty acid salt. The calcium carbonate larger in particle size
is preferably 1 .mu.m or more in particle size, and can be used
without being subjected to surface treatment.
For the purpose of improving the workability (cutting property,
etc) of the composition and deglossing the surface of the cured
substance, organic balloons and inorganic balloons are preferably
added. Such fillers can be subjected to surface treatment, and may
be used each alone or can be used in admixtures of two or more
thereof. For the purpose of improving the workability (cutting
property, etc), the particle sizes of these balloons are preferably
0.1 mm or less. For the purpose of deglossing the surface of the
cured substance, the particle sizes are preferably 5 to 300
.mu.m.
On the grounds that the cured substance of the composition of the
present invention is satisfactory in chemical resistance and the
like, the composition of present invention is suitably used for
joints of housing exterior wall such as sizing boards, in
particular, ceramic sizing boards, for a adhesive for exterior wall
tiles, for a adhesive for exterior wall tiles remaining in the
joints and for the like purposes; in this connection, it is
desirable that the design of the exterior wall and the design of
the sealant are in harmony with each other. Particularly, posh
exterior walls have come to be used by virtue of sputter coating
and mixing colored aggregates. When the composition of the present
invention is blended with a scale-like or granulated material
having a diameter of 0.1 mm or more, preferably of the order of 0.1
to 5.0 mm, the cured substance comes to be in harmony with such
posh exterior walls, and is excellent in chemical resistance, so
that the composition concerned comes to be an excellent composition
in the sense that the exterior appearance of the cured substance
remains unchanged over a long period of time. Use of a granulated
material provides a dispersed sand-like or sandstone-like surface
with a rough texture, while use of a scale-like material provides
an irregular surface based on the scale-like shape of the
material.
The preferable diameter, blended amount and materials for the
scale-like or granulated material are described in Japanese Patent
Laid-Open No. 9-53063 as follows.
The diameter is 0.1 mm or more, preferably of the order of 0.1 to
5.0 mm, and there is used a material having an appropriate size in
conformity with the material quality and pattern of exterior wall.
Materials having a diameter of the order of 0.2 mm to 5.0 mm and
materials having a diameter of the order of 0.5 mm to 5.0 mm can
also be used. In the case of a scale-like material, the thickness
is set to be as thin as the order of 1/10 to 1/5 the diameter (the
order of 0.01 to 1.00 mm). The scale-like or granulated material is
transported to the construction site as a sealant in a condition
that the material is beforehand mixed in the main component of the
sealant, or is mixed in the main component of the sealant at the
construction site when the sealant is used.
The scale-like or granulated material is blended in a content of
the order of 1 to 200 parts by weight in relation to 100 parts by
weight of a composition such as a sealant composition and an
adhesive composition. The blended amount is appropriately selected
depending on the size of the scale-like or granulated material, and
the material quality and pattern of exterior wall.
As the scale-like or granulated material, natural products such as
silica sand and mica, synthetic rubbers, synthetic resins and
inorganic substances such as alumina are used. The material is
colored in an appropriate color so as to match the material quality
and pattern of exterior wall to heighten the design quality when
filled in the joints.
A preferable finishing method and the like are described in
Japanese Patent Laid-Open No. 9-53063.
Additionally, when a balloon (preferably the mean particle size
thereof is 0.1 mm or more) is used for a similar purpose, the
surface is formed to have a dispersed sand-like or sandstone-like
surface with a rough texture, and a reduction of weight can be
achieved. The preferable diameter, blended amount and materials for
the balloon are described in Japanese Patent Laid-Open No.
10-251618 as follows.
The balloon is a sphere-shaped material with a hollow interior.
Examples of the material for such a balloon include inorganic based
materials such as glass, shirasu and silica; and organic based
materials such as phenolic resin, urea resin, polystyrene and
Saran.TM.; however, the material concerned is not limited to these
examples; an inorganic based material and an organic based material
can be compounded, or can be laminated to form multiple layers. An
inorganic based balloon, an organic based balloon, a balloon made
of a compounded inorganic-organic material or the like can be used.
Additionally, as a balloon to be used, either a type of balloon or
an admixture of multiple types of balloons can be used. Moreover, a
balloon with the processed surface thereof or with the coated
surface thereof can be used, and additionally, a balloon with the
surface thereof subjected to treatment with various surface
treatment agents can also be used. More specifically, examples are
included in which an organic based balloon is coated with calcium
carbonate, talc, titanium oxide and the like, and an inorganic
based balloon is subjected to surface treatment with a silane
coupling agent.
For the purpose of obtaining a dispersed sand-like or
sandstone-like surface with a rough texture, the particle size of
the balloon is preferably 0.1 mm or more. A balloon of a particle
size of the order of 0.2 mm to 5.0 mm or a balloon of a particle
size of the order of 0.5 mm to 5.0 mm can also be used. Use of a
balloon of a particle size of less than 0.1 mm sometimes only
increases the viscosity of the composition, and yields no rough
texture, even when the used amount of the balloon is large. The
blended amount of the balloon can be easily determined in
conformity with the desired degree of the dispersed sand-like or
sandstone-like rough texture. Usually, it is desirable that a
balloon of 0.1 mm or more in particle size is blended in a ratio of
5 to 25 vol % in terms of the volume concentration in the
composition. When the volume concentration of the balloon is less
than 5 vol %, no rough texture can be obtained, while when the
volume concentration of the balloon exceeds 25 vol %, the viscosity
of the sealant and that of the adhesive tend to become high to
degrade the workability, and the modulus of the cured substance
becomes high, so that the basic performance of the sealant and that
of the adhesive tend to be impaired. The preferable volume
concentration to balance with the basic performance of the sealant
is 8 to 22 vol %.
When a balloon is used, there can be added an antislip agent
described in Japanese Patent Laid-Open No. 2000-154368 and an amine
compound to make irregular and degloss the surface of the cured
substance described in Japanese Patent Laid-Open No. 2001-164237,
in particular, a primary amine and/or a secondary amine having a
melting point of 35.degree. C. or higher.
Specific examples of the balloon are described in the following
publications: Japanese Patent Laid-Open Nos. 2-129262, 4-8788,
4-173867, 5-1225, 7-113073, 9-53063, 10-251618, 2000-154368 and
2001-164237, and WO97/05201 pamphlet.
When the composition of the present invention includes the
particles of the cured substance derived from a sealant, the cured
substance can make irregularities on the surface to improve the
design quality. The preferable diameter, blended amount and
materials of the cured substance particle material derived from a
sealant is described in Japanese Patent Laid-Open No. 2001-115142
as follows. The diameter is preferably of the order of 0.1 mm to 1
mm, and further preferably of the order of 0.2 to 0.5 mm. The
blended amount is preferably 5 to 100 wt %, and further preferably
20 to 50 wt % in the curable composition. Examples of the materials
include urethane resin, silicone, modified silicone and polysulfide
rubber. No constraint is imposed on the materials as long as the
materials can be used as sealants; however, modified silicone based
sealants are preferable.
A plasticizer can be added to the composition of the present
invention. Addition of a plasticizer makes it possible to adjust
the viscosity and slump property of the curable composition and the
mechanical properties such as tensile strength and elongation of
the cured substance obtained by curing the composition. Examples of
the plasticizer include phthalates such as dibutyl phthalate,
diheptyl phthalate, bis(2-ethylhexyl) phthalate and butyl benzyl
phthalate; nonaroamtic dibasic acid esters such as dioctyl adipate,
dioctyl sebacate, dibutyl sebacate and diisodecyl succinate;
aliphatic esters such as butyl oleate and methyl acetylrecinoleate;
phosphates such as tricresyl phosphate and tributyl phosphate;
trimellitates; chlorinated parafins; hydrocarbon based oils such as
alkyldiphenyls and partially hydrogenated terphenyls; process oils;
epoxy plasticizer such as epoxidized soybean oil and benzyl
epoxystearate.
Additionally, a polymer plasticizer can be used. When a polymer
plasticizer is used, the initial physical properties are maintained
over a longer period of time than when a low molecular weight
plasticizer is used which is a plasticizer containing no polymer
component. Moreover, the drying property (also referred to as
coating property) can be improved when an alkyd coating material is
applied onto the cured substance concerned. Examples of the polymer
plasticizer include vinyl based polymers obtained by polymerizing
vinyl based monomers by means of various methods; polyalkylene
glycol esters such as diethylene glycol dibenzoate, triethylene
glycol dibenzoate, pentaerithritol ester; polyester based
plasticizers obtained from dibasic acids such as sebacic acid,
adipic acid, azelaic acid and phthalic acid and dihydric alcohols
such as ethylene glycol, diethylene glycol, triethylene glycol,
propylene glycol and dipropylene glycol; polyethers including
polyether polyols each having a molecular weight of 500 or more,
additionally 1000 or more such as polyethylene glycol,
polyprolylene glycol and polytetramethylene glycol, and the
derivatives of these polyether polyols in which the hydroxy groups
in these polyether polyols are substituted with ester groups, ether
groups and the like; polystyrenes such as polystyrene and
poly-.alpha.-methylstyrene; and polybutadiene, polybutene,
polyisobutylene, butadiene-acrylonitrile and polychloroprene.
However, the polymer plasticizer concerned is not limited to these
examples.
Of these polymer plasticizers, those polymer plasticizers which are
compatible with the organic polymer (A) are preferable. In this
regard, polyethers and vinyl based polymers are preferable.
Additionally, the use of polyethers as plasticizers improves the
weather resistance, surface curability and deep part curability,
and causes no curing retardation after storage, and hence
polyethers are preferable; of polyethers, polypropylene glycol is
more preferable. Additionally, from the viewpoint of the
compatibility, weather resistance and heat resistance, vinyl based
polymers are preferable. Of the vinyl based polymers, acryl based
polymers and/or methacryl based polymers are preferable, and acryl
based polymers such as polyalkylacrylate are further preferable. As
the polymerization method to produce acryl based polymers, the
living radical polymerization method is preferable because this
method can lead to narrow molecular weight distributions and low
viscosities, and the atom transfer radical polymerization method is
further preferable. Additionally, it is preferable to use a polymer
based on the so-called SGO process which is obtained by
continuously block polymerizing of an alkyl acrylate based monomer
at a high temperature and under a high pressure, as described in
Japanese Patent Laid-Open No. 2001-207157.
The number average molecular weight of the polymer plasticizer is
preferably 500 to 15000, more preferably 800 to 10000, further
preferably 1000 to 8000, particularly preferably 1000 to 5000, and
most preferably 1000 to 3000. When the molecular weight is too low,
the plasticizer is removed with time thermally and by rainfall, and
hence it is made impossible to maintain the initial physical
properties over a long period of time, and the coating property
with the alkyd coating cannot be improved. On the other hand, when
the molecular weight is too high, the viscosity becomes high and
the workability is degraded. No particular constraint is imposed on
the molecular weight distribution of the polymer plasticizer.
However, it is preferable that the molecular weight distribution is
narrow; the molecular weight distribution is preferably less than
1.80, more preferably 1.70 or less, further preferably 1.60 or
less, yet further preferably 1.50 or less, particularly preferably
1.40 or less and most preferably 1.30 or less.
The number average molecular weight of a vinyl based polymer is
measured with the GPC method, and that of a polyether based polymer
is measured with the terminal group analysis method. Additionally,
the molecular weight distribution (Mw/Mn) is measured with the GPC
method (relative to polystyrene standard).
Additionally, the polymer plasticizer either may have no reactive
silicon group or may have a reactive silicon group. When the
polymer plasticizer have a reactive silicon group, the polymer
plasticizer acts as a reactive plasticizer, and can prevent the
migration of the plasticizer from the cured substance. When the
polymer plasticizer has a reactive silicon group, the average
number of the reactive silicon group per molecule is 1 or less, and
preferably 0.8 or less. When the reactive silicon group-containing
plasticizer, in particular, a reactive silicon group-containing
oxyalkylene polymer is used, it is necessary that the number
average molecular weight thereof is lower than that of the organic
polymer (A).
The plasticizers may be used either each alone or in combinations
of two or more thereof. Additionally, a low molecular weight
plasticizer and a polymer plasticizer may be used in combination.
It is to be noted that these plasticizers can also be blended when
the polymer is produced.
The used amount of the plasticizer is 5 to 150 parts by weight,
preferably 10 to 120 parts by weight, and further preferably 20 to
100 parts by weight, in relation to 100 parts by weight of the
organic polymer (A). When the used amount is less than 5 parts by
weight, the effect as the plasticizer is not exhibited, while when
the used amount exceeds 150 parts by weight, the mechanical
strength of the cured substance is insufficient.
To the curable composition of the present invention, according to
need, there may be added a physical property regulator to regulate
the tensile strength of the produced cured substance. No particular
constraint is imposed on the physical property regulator. However,
examples of the physical property regulator include
alkylalkoxysilanes such as methyltrimethoxysilane,
dimethyldimethoxysilane, trimethylmethoxysilane and
n-propyltrimethoxysilane; alkoxysilanes having functional groups
such as alkylisopropenoxy silanes including
dimethyldiisopropenoxysilane, methyltriisopropenoxysilane,
.gamma.-glycidoxypropylmethyldiisopropenoxysilane, and
.gamma.-glycidoxypropylmethyldimethoxysilane,
.gamma.-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane,
vinyldimethylmethoxysilane, .gamma.-aminopropyltrimethoxysilane,
N-(.beta.-aminoethyl)aminopropylmethyldimethoxysilane,
.gamma.-mercaptopropyltrimethoxysilane and
.gamma.-mercaptopropylmethyldimethoxysilane; silicone varnishes;
and polysiloxanes. The use of the physical property regulator makes
it possible to increase the hardness obtained when the composition
of the present invention is cured, or to decrease the hardness to
display the elongation at break. The above described physical
property regulators may be used either each alone or in
combinations of two or more thereof.
It is to be noted that a compound to hydrolytically produce a
compound having a monovalent silanol group in the molecule thereof
has an effect to decrease the modulus of the cured substance
without degrading the stickiness of the surface of the cured
substance. Particularly, a compound to produce trimethylsilanol is
preferable. Examples of the compound to hydrolytically produce a
compound having a monovalent silanol group in the molecule thereof
include a compound described in Japanese Patent Laid-Open No.
5-117521. Additionally, examples of such a compound include a
compound which is a derivative of an alkyl alcohol such as hexanol,
octanol or decanol, and produces a silicon compound to
hydrolytically produce R.sub.3SiOH such as trimethylsilanol, and a
compound described in Japanese Patent Laid-Open No. 11-241029 which
is a derivative of a polyhydric alcohol having three or more
hydroxy groups such as trimethylolpropane, glycerin,
pentaerythritol or sorbitol, and produces a silicon compound to
hydrolytically produce R.sub.3SiOH such as trimethylsilanol.
Additionally, there can be cited such a compound as described in
Japanese Patent Laid-Open No. 7-258534 which is a derivative of
oxypropylene polymer and produces a silicon compound to
hydrolytically produce R.sub.3SiOH such as trimethylsilanol.
Moreover, there can be used a polymer described in Japanese Patent
Laid-Open No. 6-279693 which contains a hydrolyzable silicon
containing group capable of cross linking and a silicon containing
group capable of hydrolytically forming a monosilanol containing
compound.
The physical property regulator is used within a range from 0.1 to
20 parts by weight, and preferably from 0.5 to 10 parts by weight,
in relation to 100 parts by weight of the organic polymer (A).
To the curable composition of the present invention, according to
need, a thixotropy providing agent (antisagging agent) may be added
for the purpose of preventing sagging and improving workability. No
particular constraint is imposed on the antisagging agent; however,
examples of the antisagging agent include polyamide waxes;
hydrogenated castor oil derivatives; and metal soaps such as
calcium stearate, aluminum stearate and barium stearate. These
thixotropy providing agents (antisagging agents) may be used either
each alone or in combinations of two or more thereof. The tixotropy
providing agents each are used within a range from 0.1 to 20 parts
by weight in relation to 100 parts by weight of the organic polymer
(A).
In the composition of the present invention, a compound can be used
which contains an epoxy group in one molecule. Use of an epoxy
group-containing compound can increase the recovery properties of
the cured substance. Examples of the epoxy group-containing
compound include compounds such as epoxidized unsaturated oils and
fats, epoxidized unsaturated fatty acid esters, alicyclic epoxy
compounds and epichlorohydrin derivatives, and admixtures of these
compounds. More specific examples include epoxidized soybean oil,
epoxidized flaxseed oil,
bis(2-ethylhexyl)-4,5-epoxycyclohexane-1,2-dicarboxylate (E-PS),
epoxyoctyl stearate and epoxybutyl stearate. Of these, E-PS is
particularly preferable. It is recommended that these epoxy group
containing compounds each are used within a range from 0.5 to 50
parts by weight in relation to 100 parts by weight of the organic
polymer (A).
For the composition of the present invention, a photocuring
substance can be used. Use of a phtocuring substance forms a
coating film of the photocuring substance on the surface of the
cured substance to improve the stickiness and the weather
resistance of the cured substance. A photocuring substance means a
substance which undergoes a chemical change, caused by action of
light, of the molecular structure thereof in a fairly short time to
result in changes of the physical properties such as curability.
Among such a large number of compounds known are organic monomers,
oligomers, resins and compositions containing these substances, and
any commercially available substances concerned can optionally be
adopted. As representative photocuring substances, unsaturated
acryl based compounds, polyvinyl cinnamates and azidized resins and
the like can be used. The unsaturated acryl based compounds are
monomers, oligomers and admixtures of the monomers and the
oligomers, the monomers and oligomers each having one or a few
acryl or methacryl based unsaturated groups; examples of the
unsaturated acryl based compounds include monomers such as
propylene (or butylene, or ethylene)glycol di(meth)acrylate and
neopentylglycol di(meth)acrylate, and oligoesters of 10,000 or less
in molecular weight related to these monomers. Specific examples
include special acrylates (bifunctional) such as ARONIX M-210,
ARONIX M-215, ARONIX M-220, ARONIX M-233, ARONIX M-240 and ARONIX
M-245; special acrylates (trifunctional) such as ARONIX M-305,
ARONIX M-309, ARONIX M-310, ARONIX M-315, ARONIX M-320 and ARONIX
M-325; and special acrylates (multifunctional) such as ARONIX
M-400. Those compounds which each have acrylic functional groups
are particularly preferable, and additionally, those compounds
which each have, on average, three or more acrylic functional
groups in one molecule are preferable (all the aforementioned
ARONIXs are the products of Toagosei Co., Ltd.).
Examples of the polyvinyl cinnamates include photosensitive resins
having cinnamoyl groups as photosensitive groups, namely, those
compounds obtained by esterification of polyvinyl alcohol with
cinnamic acid; and additionally, a large number of derivatives of
polyvinyl cinnamates. Azidized resins are known as photosensitive
resins having azide groups as photosensitive groups; common
examples of the azidized resins include a rubber photosensitive
solution added with an azide compound as photosensitive agent, and
additionally, those compounds detailed in "photosensitive resins"
(published by Insatu Gakkai Shuppanbu, Mar. 17, 1972, p.93, p.106
and p.117); and these compounds can be used each alone or in
admixtures thereof, and in combination with sensitizers to be added
according to need. It is to be noted that addition of sensitizers
such as ketones and nitro compounds and accelerators such as amines
sometimes enhances the effect. It is recommended that the
photocuring substance is used within a range from 0.1 to 20 parts
by weight and preferably from 0.5 to 10 parts by weight in relation
to 100 parts by weight of the organic polymer (A); when the content
of the photocuring substance is less than 0.1 part by weight, no
effect to increase the weather resistance is displayed, while when
the content exceeds 20 parts by weight, the cured substance tends
to be too hard and cracked.
For the composition of the present invention, an oxygen-curable
substance can be used. Examples of the oxygen-curable substance
include unsaturated compounds reactable with the oxygen in the air,
which react with the oxygen in the air and form a cured coating
film around the surface of the cured substance to act to prevent
the surface stickiness and the sticking of dust and grime to the
surface of the cured substance and to do the like. Specific
examples of the oxygen-curable substance include drying oils
represented by wood oil, flaxseed oil and the like and various
alkyd resins obtained by modifying these compounds; acryl based
polymers, epoxy based resins and silicon resins all modified with
drying oils; liquid polymers such as 1,2-polybutadiene and
1,4-polybutadiene obtained by polymerizing or copolymerizing diene
based compounds such as butadiene, chloroprene, isoprene,
1,3-pentadiene, and polymers derived from C5 to C8 dienes, liquid
copolymers such as NBR, SBR and the like obtained by copolymerizing
these diene based compounds with monomers such as acrylonitrile,
styrene and the like having copolimerizability so as for the diene
based compounds to dominate, and various modified substance of
these compounds (maleinized modified substances, boiled
oil-modified substances, and the like). These substances can be
used either each alone or in combinations of two or more thereof.
Of these substances, wood oil and liquid diene based polymers are
particularly preferable. Additionally, in some cases, when
catalysts to accelerate the oxidation curing reaction and metal
dryers are used in combination with these substances, the effect is
enhanced. Examples of these catalysts and metal dryers include
metal salts such as cobalt naphtenate, lead naphthenate, zirconium
naphthenate, cobalt octylate and zirconium octylate; and amine
compounds. The used amount of the oxygen-curing substance is
recommended such that the oxygen-curing substance is used within a
range from 0.1 to 20 parts by weight and further preferably from
0.5 to 10 parts by weight in relation to 100 parts by weight of the
organic polymer (A); when the used amount is less than 0.1 part by
weight, improvement of staining property becomes insufficient,
while when the used amount exceeds 20 parts by weight, the tensile
property and the like of the cured substance tends to be impaired.
It is recommended that the oxygen-curing substance is used in
combination with a photocuring substance as described in Japanese
Patent Laid-Open No. 3-160053.
For the composition of the present invention, an antioxidant
(antiaging agent) can be used. Use of an antioxidant can increase
the heat resistance of the cured substance. Examples of the
antioxidant can include hindered phenol based antioxidants,
monophenol based antioxidants, bisphenol based antioxidants and
polyphenol based antioxidants, hindered phenol based antioxidants
being particularly preferable. Similarly, the following hindered
amine based photostabilizers can also be used: TINUVIN 622LD,
TINUVIN 144; CHIMASSORB944LD and CHIMASSORB119FL (all manufactured
by Ciba-Geigy Japan Ltd.); MARK LA-57, MARK LA-62, MARK LA-67, MARK
LA-63 and MARK LA-68 (all manufactured by Adeka Argus Chemical Co.,
Ltd.); and SANOL LS-770, SANOL LS-765, SANOL LS-292, SANOL LS-2626,
SANOL LS-1114 and SANOL LS-744 (all manufactured by Sankyo Co.,
Ltd.). Specific examples of the antioxidants are described also in
Japanese Patent Laid-Open Nos. 4-283259 and 9-194731. The used
amount of the antioxidant is recommended such that the antioxidant
is used within a range from 0.1 to 10 parts by weight and further
preferably from 0.2 to 5 parts by weight in relation to 100 parts
by weight of the organic polymer (A).
For the composition of the present invention, a photostabilizer can
be used. Use of a photostabilizer can prevent the photooxidation
degradation of the cured substance. Examples of the photostabilizer
include benzotriazole based compounds, hindered amine based
compounds, benzoate based compounds and the like; hindered amine
based compounds are particularly preferable. The used amount of the
photostabilizer is recommended such that the photostabilizer is
used within a range from 0.1 to 10 parts by weight and further
preferably from 0.2 to 5 parts by weight in relation to 100 parts
by weight of the organic polymer (A). Specific examples of the
photostabilizer are described in Japanese Patent Laid-Open No.
9-194731.
When the photocuring substance is used for the composition of the
present invention, in particular, when an unsaturated acryl based
compound is used, it is preferable to use a tertiary
amine-containing hindered amine based photostabilizer as a hindered
amine based photostabilizer as described in Japanese Patent
Laid-Open No. 5-70531 for the purpose of improving the storage
stability of the composition. Examples of the tertiary
amine-containing hindered amine based photostabilizer include
TINUVIN 622LD, TINUVIN 144 and CHIMASSORB119FL (all manufactured by
Ciba-Geigy Japan Ltd.); MARK LA-57, LA-62, LA-67 and LA-63 (all
manufactured by Adeka Argus Chemical Co., Ltd.); and SANOL LS-765,
SANOL LS-292, SANOL LS-2626, SANOL LS-1114 and SANOL LS-744 (all
manufactured by Sankyo Co., Ltd.).
For the composition of the present invention, an ultraviolet
absorber can be used. Use of an ultraviolet absorber can increase
the surface weather resistance of the cured substance. Examples of
the ultraviolet absorber include benzophenone based compounds,
benzotriazole based compounds, salicylate based compounds,
substituted tolyl based compounds and metal chelate based
compounds; benzotriazole based compounds are particularly
preferable. The used amount of the ultraviolet absorber is such
that the ultraviolet absorber is used within a range from 0.1 to 10
parts by weight, and further preferably from 0.2 to 5 parts by
weight in relation to 100 parts by weight of the organic polymer
(A). It is preferable that a phenol based antioxidant, a hindered
phenol based antioxidant, a hindered amine based photostabilizer
and a benzotriazole based ultraviolet absorber are used in
combination.
To the composition of the present invention, an epoxy resin can be
added. The composition added with an epoxy resin is particularly
preferable as an adhesive, in particular, an adhesive for exterior
wall tile. Examples of the epoxy resin include
epichlorohydrin-bisphenol A-type epoxy resins,
epichlorohydrin-bisphenol F-type epoxy resins, flame resistant
epoxy resins such as glycidyl ether of tetrabromobisphenol A,
novolac-type epoxy resins, hydrogenated bisphenol A-type epoxy
resins, epoxy resins of the type of glycidyl ether of bisphenol A
propyleneoxide adduct, p-oxybenzoic acid glycidyl ether ester-type
epoxy resins, m-aminophenol based epoxy resins,
diaminodiphenylmethane based epoxy resins, urethane modified epoxy
resins, various alicyclic epoxy resins, N,N-diglycidylaniline,
N,N-diglycidyl-o-toluidine, triglycidyl isocyanurate, polyalkylene
glycol diglycidyl ether, glycidyl ethers of polyhydric alcohols
such as glycerin, hydantoin-type epoxy resins and epoxidized
substances of unsaturated polymers such as petroleum resins;
however the epoxy resin is not limited to these examples, and
commonly used epoxy resins can be used. Epoxy resins having at
least two epoxy groups in one molecule are preferable because such
compositions are high in reactivity when curing is made, and the
cured substances can easily form three dimensional networks.
Examples of further preferable epoxy resins include bisphenol
A-type epoxy resins or novolac-type epoxy resins. The ratio of the
used amount of each of these epoxy resins to the used amount of the
organic polymer (A) falls, in terms of weight ratio, in the range
such that organic polymer (A)/epoxy resin=100/1 to 1/100. When the
ratio of organic polymer (A)/epoxy resin is less than 1/100, the
effect of improving the impact strength and the toughness of the
cured substance of the epoxy resin becomes hardly obtainable, while
when the ratio of organic polymer (A)/epoxy resin exceeds 100/1,
the strength of the cured substance of the organic based polymer
becomes insufficient. The preferable ratio of the used amounts is
varied depending on the application of the curable resin
composition and hence cannot be unconditionally determined; for
example, when the impact resistance, flexibility, toughness, and
peel strength and the like of the cured substance of the epoxy
resin are to be improved, it is recommended that in relation to 100
parts by weight of the epoxy resin, 1 to 100 parts by weight of the
organic polymer (A), further preferably 5 to 100 parts by weight of
the organic polymer (A) is used. On the other hand, when the
strength of the cured substance of the organic polymer (A) is to be
improved, it is recommended that in relation to 100 parts of the
organic polymer (A), 1 to 200 parts by weight of the epoxy resin,
further preferably 5 to 100 parts by weight of the epoxy resin is
used.
When the epoxy resin is added, as a matter of course, a curing
agent to cure the epoxy resin can be applied together to the
composition of the present invention. No particular constraint is
imposed on the usable epoxy resin curing agent, and commonly used
epoxy resin curing agents can be used. Specific examples of the
epoxy resin curing agent include primary and secondary amines such
as triethylenetetramine, tetraethylenepentamine,
diethylaminopropylamine, N-aminoethylpiperidine, m-xylylenediamine,
m-phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone,
isophoronediamine, and polyether with amine terminal groups;
tertiary amines such as 2,4,6-tris(dimethylaminomethyl)phenol and
tripropylamine, and salts of the tertiary amines; polyamide resins;
imidazoles; dicyandiamides; borontrifluoride complexes; carboxylic
anhydrides such as phthalic anhydride, hexahydrophthalic anhydride,
tetrahydrophthalic anhydride, dodecynylsuccinic anhydride,
pyromellitic anhydride and chlorendic anhydride; alcohols; phenols;
carboxylic acids; and diketone complexes of aluminum and zirconium.
However, the epoxy resin curing agent is not limited to these
examples. Additionally, the curing agents may be used either each
alone or in combinations of two or more thereof.
When an epoxy resin curing agent is used, the used amount thereof
falls within a range from 0.1 to 300 parts by weight in relation to
100 parts by weight of the epoxy resin.
As an epoxy resin curing agent, a ketimine can be used. A ketimine
is stable when no moisture is present, but moisture decomposes the
ketimine into a primary amine and a ketone; the thus produced
primary amine acts as a room temperature curable curing agent to
cure the epoxy resin. Use of a ketimine makes it possible to obtain
a one-component composition. Such a ketimine can be obtained by
condensation reaction between an amine compound and a carbonyl
compound.
For the synthesis of a ketimine, an amine compound and a carbonyl
compound well known in the art can be used. For example, the
following compounds can be used as such an amine compound: diamines
such as ethylenediamine, propylenediamine, trimethylenediamine,
tetramethylenediamine, 1,3-diaminobutane, 2,3-diaminobutane,
pentamethylenediamine, 2,4-diaminopentane, hexamethylenediamine,
p-phenylenediamine and p,p'-biphenylenediamine; polyvalent amines
such as 1,2,3-triaminopropane, triaminobenzene,
tris(2-aminoethyl)amine and tetra(aminomethyl)methane;
polyalkylenepolyamines such as diethylenetriamine,
triethylenetriamine and tetraethylenepentamine; polyoxyalkylene
based polyamines; and aminosilanes such as
.gamma.-aminopropyltriethoxysilane,
N-(.beta.-aminoethyl)-.gamma.-aminopropyltrimethoxysilane and
N-(.beta.-aminoethyl)-.gamma.-aminopropylmethyldimethoxysilane.
Additionally, the following compounds can be used as such a
carbonyl compound: aldehydes such as acetoaldehyde,
propionaldehyde, n-butylaldehyde, isobutylaldehyde,
diethylacetoaldehyde, glyoxal and benzaldehyde; cyclic ketones such
as cyclopentanone, trimethylcyclopentanone, cyclohexanone and
trimethylcyclohexanone; aliphatic ketones such as acetone, methyl
ethyl ketone, methyl propyl ketone, methyl isopropyl ketone, methyl
isobutyl ketone, diethyl ketone, dipropyl ketone, diisopropyl
ketone, dibutyl ketone and diisobutyl ketone; and .beta.-dicarbonyl
compounds such as acetylacetone, methyl acetoacetate, ethyl
acetoacetate, dimethyl malonate, diethyl malonate, methyl ethyl
malonate and dibenzoylmethane.
When an imino group is present in the ketimine, the imino group can
be reacted with styrene oxide; glycidyl ethers such as butyl
glycidyl ether and allyl glycidyl ether; and glycidyl esters. These
ketimines may be used either each alone or in combinations of two
or more thereof; these ketimines each used within a range of 1 to
100 parts by weight in relation to 100 parts by weight of the epoxy
resin, the used amount of each of the ketimines is varied depending
on the type of the epoxy resin and the type of the ketimine.
To the curable composition of the present invention, various
additives can be added according to need for the purpose of
regulating the physical properties of the curable composition or
the cured substance. Examples of such additives include flame
retardants, curing regulators, radical inhibitors, metal
deactivators, antiozonants, phosphorus based peroxide decomposers,
lubricants, pigments, foaming agents, solvents and mildewproofing
agents. These various additives may be used either each alone or in
combinations of two or more thereof. Specific additive examples
other than the specific examples cited in the present specification
are described, for example, in Japanese Patent Publication Nos.
4-69659 and 7-108928, Japanese Patent Laid-Open Nos. 63-254149,
64-22904, 2001-72854 and the like.
The curable composition of the present invention can also be
prepared as a one component-type composition curable after
application with moisture in the air in such a way that all the
blended components are beforehand blended together and hermetically
stored. The curable composition of the present invention can also
be prepared as two component-type composition in such a way that a
compound agent is prepared as a curing agent by blending together a
curing catalyst, a filler, a plasticizer and water, and the thus
blended material is mixed with a polymer composition before use.
From the viewpoint of workability, a one component-type composition
is preferable.
When the above described curable composition is of the one
component-type, all the blended components are blended together
beforehand, so that it is preferable that the blended components
containing moisture are used after dehydrating and drying, or the
components are dehydrated by reducing pressure or the like while
being kneaded for blending. When the above described curable
composition is of the two component-type, it is not necessary to
blend a curing catalyst with the main component containing a
reactive silicon group-containing polymer, and hence there is
little fear of gelation even when some moisture is contained in the
blended components; however, when a long term storage stability is
required, it is preferable to carry out dehydration and drying. As
for the methods of dehydration and drying, a thermal drying method
is suitable for a powdery solid substance or the like, while a
reduced pressure dehydration method or a dehydration method which
uses a synthetic zeolite, active alumina or silica gel is suitable
for a liquid substance. Additionally, there can be adopted a method
in which a small amount of an isocyanate compound is added to make
its isocyanate group react with water for dehydration. In addition
to these dehydration and drying methods, addition of the following
compounds further improves the storage stability: lower alcohols
such as methanol and ethanol; and alkoxysilane compounds such as
n-propyltrimethoxysilane, vinyltrimethoxysilane,
vinylmethyldimethoxysilane,
.gamma.-mercaptopropylmethyldimethoxysilane,
.gamma.-mercaptopropylmethyldiethoxysilane and
.gamma.-glycidoxypropyltrimethoxysilane.
It is particularly preferable that the used amount of a dehydrating
agent, in particular, a silicon compound capable of reacting with
water such as vinyltrimethoxysilane falls within a range from 0.1
to 20 parts by weight, and preferably 0.5 to 10 parts by weight in
relation to 100 parts by weight of the organic polymer (A).
No particular constraint is imposed on the preparation method of
the curable composition of the present invention; for example,
there can be adopted a common method in which the above described
components are blended together and kneaded with a mixer, a roll or
a kneader at room temperature or under heating, or a common method
in which the above described components are dissolved and mixed by
use of a small amount of an appropriate solvent.
The curable composition of the present invention forms three
dimensional networks when exposed to the air due to the action of
the moisture to be cured into a solid matter having a rubber-like
elasticity.
The curable composition of the present invention can be used as a
one-component curable composition, a one-component curable
composition being preferable from the viewpoint of workability.
The curable composition of the present invention can be used as
tackifiers, sealants for buildings, ships, vehicles and road,
adhesives, mold forming materials, vibration proof material,
dumping materials, soundproof materials, foaming materials, coating
materials, spraying materials and the like. Additionally, the
curable composition of the present invention can be used in various
applications as liquid sealants to be used in materials for
electric and electronic components such as backside sealants for
solar cells, electric insulating materials such as insulating
coating materials for use in electric wire and cable, elastic
adhesives, powdery coating materials, casting materials, medical
rubber materials, medical adhesives, medical instrument sealants,
food packaging materials, sealants for joints in exterior materials
such as sizing boards, coating materials, primers, electromagnetic
wave shielding conductive materials, heat conducting materials, hot
melt materials, electric and electronic potting agents, films,
gaskets, various molding materials, antirust and waterproof
sealants for edges (cut portions) of wire glass and laminated
glass, vehicle components, electric appliance components, various
machinery components and the like. Moreover, the curable
composition of the present invention can adhere alone or in
combination with a primer to a wide variety of substrates including
glass, porcelain, woods, metals and molded resin articles, and
accordingly, can be used as various types of sealing and adhesive
compositions. Additionally, the curable composition of the present
invention is excellent in recovery properties, durability and creep
resistance, and hence is particularly preferable when used as
adhesives for interior panels, adhesive for exterior panels,
adhesives for tiling, adhesives for stone tiling, adhesives for
finishing ceiling, adhesives for finishing floor, adhesives for
finishing wall, adhesives for vehicle panels, adhesives for
assembling electric, electronic and precision instruments, sealants
for direct glazing, sealants for double glazing, sealants for the
SSG technique and sealants for working joints of buildings.
In the next place, the present invention is specifically described
on the basis of examples and comparative examples, but the present
invention is not limited by these examples and comparative
examples.
SYNTHESIS EXAMPLE 1
By use of a polyoxypropylene triol having a molecular weight of
about 3,000 as an initiator and zinc hexacyanocobaltate-glyme
complex as a catalyst, polymerization of propylene oxide was
carried out to yield a polypropylene oxide having a number average
molecular weight of about 26,000 (a molecular weight relative to
polystyrene standard measured by using a HLC-8120 GPC manufactured
by Tosoh Corp. as a liquid delivery system, a column of TSK-GEL
H-type manufactured by Tosoh Corp., and THF as a solvent). Then, a
methanol solution of NaOMe was added in an amount of 1.2
equivalents in relation to the hydroxy group of the above hydroxy
group-terminated polypropylene oxide, the methanol was distilled
off, and allyl chloride was further added to thereby convert the
terminal hydroxy group into an allyl group. The unreacted allyl
chloride was distilled off under reduced pressure. To 100 parts by
weight of the obtained, crude allyl-terminated polypropylene diol,
300 parts by weight of n-hexane and 300 parts by weight of water
were added. The mixture thus obtained was stirred to mix, and then
the water was removed by centrifugal separation. To the hexane
solution thus obtained, 300 parts by weight of water was further
added, the mixture thus obtained was stirred to mix, the water was
again removed by centrifugal separation, and then the hexane was
distilled off under reduced pressure. Thus, an allyl
group-terminated trifunctional polypropylene oxide having a number
average molecular weight of about 26,000 was obtained.
In a 1 L autoclave, 500 g of the above obtained allyl-terminated
trifunctional polypropylene oxide and 10 g of hexane were placed,
and the mixture thus obtained was subjected to azeotropic
dehydration at 90.degree. C. The hexane was distilled off under
reduced pressure and the autoclave was purged with nitrogen. To the
contents of the autoclave, 30 .mu.l of platinum divinyldisiloxane
complex (a 3 wt % solution in xylene in terms of platinum) was
added, and then 7.0 g of dimethoxymethylsilane was added dropwise.
The mixed solution thus obtained was allowed to react at 90.degree.
C. for 2 hours, and then the unreacted dimethoxymethylsilane was
distilled off under reduced pressure to yield a reactive silicon
group-containing polyoxyalkylene based polymer (A-1). The number
average molecular weight of the obtained polymer (A-1) was 26,000.
Additionally, the silylation ratio was measured on the basis of
.sup.1H-NMR (measured in CDCl.sub.3 as solvent by use of a
JNM-LA400 spectrometer manufactured by JEOL) with the aid of the
following method. The silylation ratio was found to be 78% on the
basis of the ratio between the following two relative values
<1> and <2>, namely, <2>/<1>: the relative
value <1> of the integrated peak intensity of the allyl
terminal protons (CH.sub.2.dbd.CH--CH.sub.2--: around 5.1 ppm) to
the integrated peak intensity of the CH.sub.3 group (around 1.2
ppm) in the polypropylene oxide main chain in the above described
allyl-terminated trifunctional polypropylene oxide before
hydrosilylation reaction, and the relative value <2> of the
integrated peak intensity of the protons
(CH.sub.3(CH.sub.3O).sub.2Si--CH.sub.2--CH.sub.2--: around 0.6 ppm)
of the methylene group bonded to the silicon atom of the terminal
silyl group to the integrated peak intensity of the CH.sub.3 group
(around 1.2 ppm) in the polypropylene oxide main chain in the
silyl-terminated polypropylene oxide (A-1) after hydrosilylation
reaction.
SYNTHESIS EXAMPLE 2
To 500 g of a polyoxypropylene glycol having a number average
molecular weight of 3,000, 40 g of sodium hydroxide was added, and
the mixture thus obtained was allowed to react at 60.degree. C. for
13 hours. Then, to the reaction mixture, 11.7 g of
bromochloromethane was added and the mixture was allowed to react
at 60.degree. C. for 10 hours. The Mw/Mn value and the viscosity of
the obtained polymer were 2.1 and 160 poises, respectively.
Successively, 8.5 g of ally chloride was added to the polymer and
the mixture thus obtained was allowed to react for 36 hours, and
then subjected to adsorption treatment with aluminum silicate. To
500 g of this polymer, a chloroplatinic acid catalyst was added,
then 7.5 g of dimethoxymethylsilane was added, and the mixture thus
obtained was allowed to react at 80.degree. C. for 4 hours to yield
a pale yellow, reactive silicon group-containing polyoxyalkylene
based polymer (A-2).
SYNTHESIS EXAMPLE 3
To a mixture of 420 g of a polyoxypropylene glycol having a number
average molecular weight of 3,000 and 80 g of a polyoxypropylene
triol having a number average molecular weight of 3,000, 40 g of
sodium hydroxide was added, and the mixture thus obtained was
allowed to react at 60.degree. C. for 13 hours. Then, to the
reaction mixture, 19 g of bromochloromethane was added and the
mixture was allowed to react at 60.degree. C. for 10 hours. The
Mw/Mn value and the viscosity of the obtained polymer were 2.1 and
385 poises, respectively. Successively, 15 g of ally chloride was
added to the polymer and the mixture thus obtained was allowed to
react for 36 hours, and then subjected to adsorption treatment with
aluminum silicate. To 500 g of this polymer, a chloroplatinic acid
catalyst was added, then 12 g of dimethoxymethylsilane was added,
and the mixture thus obtained was allowed to react at 80.degree. C.
for 4 hours to yield a pale yellow, reactive silicon
group-containing polyoxyalkylene based polymer (A-3).
SYNTHESIS EXAMPLE 4
By use of a 1/1 (weight ratio) mixture of a polyoxypropylene diol
having a molecular weight of about 2,000 and a polyoxypropylene
triol having a molecular weight of about 3,000 as an initiator and
zinc hexacyanocobaltate-glyme complex as a catalyst, polymerization
of propylene oxide was carried out to yield a polypropylene oxide
having a number average molecular weight of about 19,000 (a
molecular weight relative to polystyrene standard measured by using
a HLC-8120 GPC manufactured by Tosoh Corp. as a liquid delivery
system, a column of TSK-GEL H-type manufactured by Tosoh Corp., and
THF as a solvent). Then, a methanol solution of NaOMe was added in
an amount of 1.2 equivalents in relation to the hydroxy group of
the above hydroxy-terminated polypropylene oxide, the methanol was
distilled off, and allyl chloride was further added to thereby
convert the terminal hydroxy group into an allyl group. Thus, an
allyl group-terminated polypropylene oxide having a number average
molecular weight of about 19,000 was obtained.
To 100 parts by weight of the obtained, crude allyl-terminated
polypropylene oxide, 300 parts by weight of n-hexane and 300 parts
by weight of water were added. The mixture thus obtained was
stirred to mix, and then the water was removed by centrifugal
separation. To the hexane solution thus obtained, 300 parts by
weight of water was further added, the mixture thus obtained was
stirred to mix, the water was again removed by centrifugal
separation, and then the hexane was distilled off under reduced
pressure to yield a purified, allyl group-terminated polypropylene
oxide (hereinafter referred to as allyl polymer). To 100 g of the
obtained allyl polymer, an isopropyl alcohol solution of platinum
vinylsiloxane complex of 3 wt % in terms of platinum was added as a
catalyst in 150 ppm, and the allyl polymer was reacted with 1.35
parts by weight of methyldimethoxysilane at 90.degree. C. for 5
hours to yield a reactive silicon group-containing polyoxyalkylene
based polymer (A-4).
EXAMPLES 1 AND 2, AND COMPARATIVE EXAMPLE 1
The reactive silicon group-containing polyoxyalkylene based polymer
(A-1) obtained in Synthesis Example 1 was used as the organic
polymer (A), and fillers, plasticizers, a thixotropy providing
agent, a surface modifier, an ultraviolet absorber and an
antioxidant were weighed out respectively according to the
formulations shown in Table 1; then, all these ingredients were
fully kneaded together with a three-roll paint mill to yield each
main component.
Then, various carboxylic acids (B) and laurylamine as the amine
compound (E) were weighed out as the silanol condensation catalysts
and added to the main components, and the mixtures thus obtained
were stirred with a spatula for 3 minutes to mix together. After
mixing, the thus obtained compositions each were filled in a
molding frame of about 5 mm in thickness with the aid of a spatula,
and the surface of each of the filled compositions was fully
flattened. The planarization completion time was set as the curing
starting time; every one minute, the surface of each of the
compositions was touched with a spatula, and the skin formation
time was measured as the time when the composition no longer stuck
to the spatula. Moreover, the tack free time was measured as the
time when the composition no longer adhered to the finger when
touched with a finger.
The compositions of the main components and the curing catalysts,
and the measured results of the skin formation time and the tack
free time are shown in Table 1.
TABLE-US-00001 TABLE 1 Ex. Comp. ex. Composition (parts by weight)
1 2 1 Organic polymer (A) A-1 95 95 95 Filler Hakuenka CCR.sup.(1)
Shiraishi Kogyo Kaisha, Ltd. 60 60 60 Viscolite-R.sup.(1) Shiraishi
Kogyo Kaisha, Ltd. 60 60 60 Whiton SB.sup.(2) Shiraishi Calcium
Kaisha, Ltd. 20 20 20 Plasticizer DOP.sup.(3) Kyowa Hakko Co., Ltd.
40 40 40 Sansocizer E-PS.sup.(4) New Japan Chemical Co., Ltd. 20 20
20 Thixotropy providing agent Disparlon #305.sup.(5) Kusumoto
Chemicals, Ltd. 3 3 3 Surface modifier Aronix M-309.sup.(6)
Toagosei Co., Ltd. 3 3 3 Ultraviolet absorber Tinuvin 327.sup.(7)
Ciba-Geigy Ltd. 1 1 1 Antioxidant Irganox 1010.sup.(8) Ciba-Geigy
Ltd. 1 1 1 Carboxylic Carboxylic Pivalic acid.sup.(9) Wako Pure
Chemical Industries, Ltd. 3 acid (B) acid (C) Versatic 10.sup.(10)
Japan Epoxy Resin Co., Ltd. 3 2-Ethylhexanoic acid Wako Pure
Chemical Industries, Ltd. 3 Amine compound (E) Laurylamine Wako
Pure Chemical Industries, Ltd. 0.75 0.75 0.75 Curing time Skin
formation time (min) 82 83 130 Tack free time (min) 86 85 133
.sup.(1)Precipitated calcium carbonate .sup.(2)Ground calcium
carbonate .sup.(3)Bis(2-ethylhexyl) phthalate
.sup.(4)Bis(2-ethylhexyl) epoxyhexahydrophthalate
.sup.(5)Hydrogenated castor oil .sup.(6)Trimethylolpropane
triacrylate
.sup.(7)2-(3,5-Di-t-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole
.sup.(8)Pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxypheny)propiona-
te .sup.(9)Neopentanoic acid .sup.(10)Neodecanoic acid
As shown in Table 1, excellent curabilities were displayed in the
cases of Examples 1 and 2 each using, as the silanol condensation
catalyst, a carboxylic acid in which the carbon atom adjacent to
the carbonyl group is a quaternary carbon atom, as compared to
Comparative Example 1 using, as the silanol condensation catalyst,
2-ethylhexanoic acid which is a carboxylic acid in which the carbon
atom adjacent to the carbonyl group is a tertiary carbon atom.
EXAMPLES 3 AND 4, AND COMPARATIVE EXAMPLES 2 AND 3
The reactive silicon group-containing polyoxyalkylene based
polymers (A-2, A-3) respectively obtained in Synthesis Example 2
and Synthesis Example 3 were used as the organic polymer (A), and a
filler, titanium oxide, a plasticizer, an antisagging agent, an
ultraviolet absorber and a photostabilizer were weighed out
respectively according to the formulations shown in Table 2; then,
all these ingredients were fully kneaded together with a three-roll
paint mill to yield each main component.
Then, a dehydrating agent, an adhesion-imparting agent, and various
carboxylic acids each as the silanol condensation catalyst were
weighed out, and moreover, laurylamine was used simultaneously as
the amine compound (E); and all these ingredients were added to the
main components, and the mixtures thus obtained were stirred with a
spatula for 3 minutes to mix together. After mixing, the thus
obtained compositions each were filled in a molding frame of about
5 mm in thickness with the aid of a spatula, and the surface of
each of the filled compositions was fully flattened. The skin
formation time and the tack free time were measured.
TABLE-US-00002 TABLE 2 Ex. Comp. ex. Composition (parts by weight)
3 4 2 3 Organic polymer (A) A-2 60 60 60 60 A-3 40 40 40 40 Filler
Hakuenka CCR.sup.(1) Shiraishi Kogyo Kaisha, Ltd. 120 120 120 120
Titanium oxide Tipaque R-820 Ishihara Sangyo Kaisha, Ltd. 20 20 20
20 Plasticizer DIDP.sup.(2) Kyowa Hakko Co., Ltd. 55 55 55 55
Antisagging agent Disparlon #6500.sup.(3) Kusumoto Chemicals, Ltd.
2 2 2 2 Ultraviolet absorber Tinuvin 327.sup.(4) Ciba-Geigy Ltd. 1
1 1 1 Photostabilizer Sanol LS-770.sup.(5) Sankyo Co., Ltd. 1 1 1 1
Dehydrating agent A-171.sup.(6) Japan Unicar Co., Ltd. 2 2 2 2
Adhesion-imparting agent A-1120.sup.(7) Japan Unicar Co., Ltd. 3 3
3 3 Carboxylic Carboxylic Versatic 10.sup.(9) Japan Epoxy Resin
Co., Ltd. 3 6 acid (B) acid (C) 2-Ethylhexanoic Wako Pure Chemical
Industries, Ltd. 3 6 acid Amine compound (E) Laurylamine Wako Pure
Chemical Industries, Ltd. 0.75 1.5 0.75 1.5 Curing time Skin
formation time (hr:min) 3:50 1:32 >8:00 3:50 Tack free time
(hr:min) 4:01 1:37 >8:00 4:04 .sup.(1)Precipitated calcium
carbonate .sup.(2)Diisodecyl phthalate .sup.(3)Fatty acid amide wax
.sup.(4)2-(3,5-Di-t-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole
.sup.(5)Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate
.sup.(6)Trimethoxyvinylsilane
.sup.(7)H.sub.2NC.sub.2H.sub.4NHC.sub.3H.sub.6Si(OMe).sub.3
.sup.(8)Neopentanoic acid .sup.(9)Neodecanoic acid
As shown in Table 2, Example 3 in which 3 parts of Versatic 10,
namely, a carboxylic acid in which the carbon atom adjacent to the
carbonyl group is a quaternary carbon atom was added displayed a
better curability than Comparative Example 2 in which
2-ethylhexanoic acid, namely, a carboxylic acid in which the carbon
atom adjacent to the carbonyl group is a tertiary carbon atom was
used; a further increase of the added amount by a factor of 2
provided a more practical curing time (Example 4).
EXAMPLE 5 AND COMPARATIVE EXAMPLES 4 AND 5
The reactive silicon group-containing polyoxyalkylene based polymer
(A-4) obtained in Synthesis Example 4 was used as the organic
polymer (A), and a filler, titanium oxide, a plasticizer, an
antisagging agent, an ultraviolet absorber, a photostabilizer, a
dehydrating agent and an adhesion-imparting agent were weighed out,
and a carboxylic acid, an organotin compound and an amine compound
(E) were also weighed out to be used as the curing catalysts,
according to the formulations shown in Table 3; all these
ingredients were mixed together with a mixer to prepare
one-component curable compositions, which were sealed in aluminum
cartridges.
By use of the prepared one-component curable compositions, various
physical properties were investigated on the basis of the following
procedures.
(Curing Test)
The curable compositions each were extruded from the cartridge and
filled in a molding frame of about 5 mm in thickness with a
spatula; the surface of each of the filled compositions was fully
flattened, and the planarization completion time was set as the
curing starting time. Every one minute, the surface of each of the
compositions was touched with a spatula, and the skin formation
time was measured as the time when the composition no longer stuck
to the spatula.
(Recovery Ratio)
The curable compositions each were filled in a sheet-shaped molding
frame of 3 mm in thickness, the surface of each of the compositions
was fully flattened, and the compositions were aged at 23.degree.
C. for 3 days and additionally at 50.degree. C. for 4 days. The
aged compositions each were blanked into a dumbbell-shaped cured
substance by use of a dumbbell-shaped die. Reference lines were
marked with an interval of 20 mm on the pinched-in portion of each
of the dumbbell-shaped specimens thus obtained. These specimens
were fixed under a condition of 100% elongation at a constant
temperature of 60.degree. C. so that the reference line interval
changed from 20 mm to 40 mm. After 24 hours, the fixation was
released and the specimens were allowed to stand still in a
temperature-controlled room at 23.degree. C.; the recovery ratios
after 1 hour were measured. The results obtained are shown in Table
3.
(Adhesion Test)
The curable compositions each were extruded from the cartridge so
that the compositions each were adhered to an adherend shown in
Table 3, and were aged at 23.degree. C. for 7 days. Thereafter, the
compositions were subjected to a 90 degree hand peel test. The
breakdown conditions of the cured substances were observed and the
cohesion failure rates (CF rates) were investigated. In the table,
A, B, C, and D denote the CF rates of 100%, 50% or more, less than
50% and the 100% interface peeling, respectively. The results
obtained are shown in Table 3.
TABLE-US-00003 TABLE 3 Ex. Comp. ex. Composition (parts by weight)
5 4 5 Organic polymer (A) A-4 100 100 100 Filler Hakuenka
CCR.sup.(1) Shiraishi Kogyo Kaisha, Ltd. 120 120 120 Titanium oxide
Tipaque R-820 Ishihara Sangyo Kaisha, Ltd. 20 20 20 Plasticizer
DIDP.sup.(2) Kyowa Hakko Co., Ltd. 55 55 55 Antisagging agent
Disparlon #6500.sup.(3) Kusumoto Chemicals, Ltd. 2 2 2 Ultraviolet
absorber Tinuvin 327.sup.(4) Ciba-Geigy Ltd. 1 1 1 Photostabilizer
Sanol LS-770.sup.(5) Sankyo Co., Ltd. 1 1 1 Dehydrating agent
A-171.sup.(6) Japan Unicar Co., Ltd. 2 2 2 Adhesion-imparting agent
A-1120.sup.(7) Japan Unicar Co., Ltd. 3 3 3 Carboxylic Carboxylic
Versatic 10.sup.(8) Japan Epoxy Resin Co., Ltd. 2.5 acid (B) acid
(C) 2-Ethylhexanoic acid Wako Pure Chemical Industries, 2.5 Ltd.
Amine compound (E) DEAPA.sup.(9) Wako Pure Chemical Industries, 1 1
Ltd. Organotin compound Neostann U-220.sup.(10) Nitto Kasei Co.,
Ltd. 2 Curability Skin formation time (min) 88 225 22 Adhesion 90
Degree hand peel Glass A A A Anode oxidized aluminum A D A Aluminum
A C A Stainless steel plate B D B FRP B C A Recovery ratio (%) 63
64 26 .sup.(1)Precipitated calcium carbonate .sup.(2)Diisodecyl
phthalate .sup.(3)Fatty acid amide wax
.sup.(4)2-(3,5-Di-t-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole
.sup.(5)Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate
.sup.(6)Trimethoxyvinylsilane
.sup.(7)H.sub.2NC.sub.2H.sub.4NHC.sub.3H.sub.6Si(OMe).sub.3
.sup.(8)Neodecanoic acid .sup.(9)3-Diethylaminopropylamine
.sup.(10)Dibutyltin(IV) bisacetylacetonate Metal(Sn) content:
27.5%
As shown in Table 3, an excellent curability was obtained in the
case in which the carboxylic acid (C) was used as the silanol
condensation catalyst, as compared to Comparative Example 4 in
which 2-ethylhexanoic acid was used; moreover, the adhesion was
also satisfactory.
As Comparative Example 5 shows, the recovery ratio was poor when
Neostann U-220, an organotin compound, was used as the silanol
condensation catalyst. On the contrary, satisfactory recoveries
were displayed in the cases each using a carboxylic acid as in
Example 5 and Comparative Example 4.
EXAMPLES 6 TO 8 AND COMPARATIVE EXAMPLES 6 AND 7
The reactive silicon group-containing polyoxyalkylene based polymer
(A-4) obtained in Synthesis Example 4 was used as the organic
polymer (A), and a filler, a plasticizer, a thixotropy providing
agent, a surface modifier, an ultraviolet absorber and an
antioxidant were weighed out, respectively, according to the
formulations shown in Table 4; then, all these ingredients were
fully kneaded together with a three-roll paint mill to yield each
main component.
Then, as shown in Table 4, a metal carboxylate, a carboxylic acid
(B) and an amine compound (E) were weighed out as the silanol
condensation catalysts, and added to the main components, and the
mixtures thus obtained were stirred with a spatula for 3 minutes to
mix together. After mixing, the thus obtained compositions each
were filled in a molding frame of about 5 mm in thickness with the
aid of a spatula, and the surface of each of the filled
compositions was fully flattened. The planarization completion time
was set as the curing starting time; every one minute, the surface
of each of the compositions was touched with a spatula, and the
skin formation time was measured as the time when the composition
no longer stuck to the spatula.
The compositions of the main component and the curing catalyst, and
the measured results of the skin formation time are shown in Table
4.
TABLE-US-00004 TABLE 4 Ex. Comp. Ex. Composition (parts by weight)
6 7 8 6 7 Organic polymer (A) A-4 100 100 100 100 100 Filler
Hakuenka CCR.sup.(1) Shiraishi Kogyo Kaisha, Ltd. 120 120 120 120
120 Titanium oxide Tipaque R-820 Ishihara Sangyo Kaisha, Ltd. 20 20
20 20 20 Plasticizer DIDP.sup.(2) Kyowa Hakko Co., Ltd. 55 55 55 55
55 Antisagging agent Disparlon #6500.sup.(3) Kusumoto Chemicals,
Ltd. 2 2 2 2 2 Ultraviolet absorber Tinuvin 327.sup.(4) Ciba-Geigy
Ltd. 1 1 1 1 1 Photostabilizer Sanol LS-770.sup.(5) Sankyo Co.,
Ltd. 1 1 1 1 1 Metal carboxylate Neostann U-50.sup.(6) Nitto Kasei
Co., Ltd. 3.4 3.4 3.4 Neostann U-28.sup.(7) Nitto Kasei Co., Ltd. 3
3 Carboxylic acid (B) Versatic 10.sup.(8) Japan Epoxy Resin Co.,
Ltd. 1.2 1.2 2-Ethyhexanoic acid Wako Pure Chemical Industries, 1 1
Ltd. Amine compound (E) Laurylamine Wako Pure Chemical Industries,
0.75 0.75 0.75 0.75 0.75 Ltd. Curing time Skin formation time (min)
60 75 92 120 103 .sup.(1)Precipitated calcium carbonate
.sup.(2)Diisodecyl phthalate .sup.(3)Fatty acid amide wax
.sup.(4)2-(3,5-Di-t-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole
.sup.(5)Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate
.sup.(6)Tin(II) neodecanoate Metal(Sn) content: 22 to 24%
.sup.(7)Tin(II) 2-ethylhexanoate Metal(Sn) content: 28%
.sup.(8)Neodecanoic acid
As shown in Table 4, the skin formation time was found to be
shorter in the case in which, as in Examples 6, 7 and 8, at least
one of the carboxylic acid having the acid radical of a metal
carboxylate and the carboxylic acid (B), to be used as silanol
condensation catalysts, is a carboxylic acid in which the carbon
atom adjacent to the carbonyl group is a quaternary carbon atom, as
compared to Comparative Example 6 in which as silanol condensation
catalysts, Neostann U-28 which is a metal carboxylate in which the
carbon atom adjacent to the carbonyl group is a tertiary carbon
atom and 2-ethylhexanoic acid which is a carboxylic acid in which
the carbon atom adjacent to the carbonyl group is a tertiary carbon
atom were used. Additionally, when as in Comparative Example 7,
only the metal carboxylate (D) was used, but the carboxylic acid
(B) was not used, the curability was degraded.
EXAMPLES 9 TO 11 AND COMPARATIVE EXAMPLE 8
The reactive silicon group-containing polyoxyalkylene based polymer
(A-4) obtained in Synthesis Example 4 was used as the organic
polymer (A), and a filler, titanium oxide, a plasticizer, an
antisagging agent, an ultraviolet absorber, a photostabilizer, a
dehydrating agent and an adhesion-imparting agent were weighed out,
and a carboxylic acid (B), a metal carboxylate (D), an amine
compound (E) and an organotin catalyst were also weighed out to be
used as the curing catalysts, according to the formulations shown
in Table 5; all these ingredients were mixed together with a mixer
to prepare one liquid curable compositions, which were sealed in
aluminum cartridges.
The curable compositions each were extruded from the cartridge and
filled in a molding frame of about 5 mm in thickness with a
spatula; the surface of each of the filled compositions was
flattened, and the skin formation time was measured.
Additionally, dumbbell-shaped cured specimens of 3 mm in thickness
were prepared, and the cured specimens were fixed under a condition
of 100% elongation at a constant temperature of 60.degree. C. After
24 hours, the fixation was released and the specimens were allowed
to stand still in a temperature-controlled room at 23.degree. C.;
the recovery ratios after 1 hour were measured. The results
obtained are shown in Table 5. In the table, A, B, and C denote the
recoveries of 60% or more, 30% or more and less than 60%, and less
than 30%, respectively.
TABLE-US-00005 TABLE 5 Ex. Comp. ex. Composition (parts by weight)
9 10 11 8 5 Organic polymer A-4 100 100 100 100 100 (A) Filler
Hakuenka CCR.sup.(1) Shiraishi Kogyo Kaisha, Ltd. 120 120 120 120
120 Titanium oxide Tipaque R-820 Ishihara Sangyo Kaisha, Ltd. 20 20
20 20 20 Plasticizer DTDP.sup.(2) Kyowa Hakko Co., Ltd. 55 55 55 55
55 Antisagging agent Disparlon #6500.sup.(3) Kusumoto Chemicals,
Ltd. 2 2 2 2 2 Ultraviolet Tinuvin 327.sup.(4) Ciba-Geigy Ltd. 1 1
1 1 1 absorber Photostabilizer Sanol LS-770.sup.(5) Sankyo Co.,
Ltd. 1 1 1 1 1 Dehydrating agent A-171.sup.(6) Japan Unicar Co.,
Ltd. 2 2 2 2 2 Adhesion-imparting A-1120.sup.(7) Japan Unicar Co.,
Ltd. 3 3 3 3 3 agent Metal carboxylate Neostann U-50.sup.(8) Nitto
Kasei Co., Ltd. 3.4 3.4 3.4 3.4 (D) Carboxylic acid Versatic
10.sup.(9) Japan Epoxy Resin Co., Ltd. 1 1.2 (B) 2-Ethylhexanoic
Wako Pure Chemical Industries, 1 acid Ltd. Amine compound (E)
Laurylamine Wako Pure Chemical Industries, 0.75 0.75 0.75 0.75 Ltd.
Organotin Neostann U-220.sup.(10) Nitto Kasei Co., Ltd. 2 Curing
time Skin formation time (min) 76 62 91 103 22 Recovery ratio (%) A
A A A C .sup.(1)Precipitated calcium carbonate .sup.(2)Diisodecyl
phthalate .sup.(3)Fatty acid amide wax
.sup.(4)2-(3,5-Di-t-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole
.sup.(5)Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate
.sup.(6)Trimethoxyvinylsilane
.sup.(7)H.sub.2NC.sub.2H.sub.4NHC.sub.3H.sub.6Si(OMe).sub.3
.sup.(8)Tin(II) neodecanoate Metal(Sn) content: 22 to 24%
.sup.(9)Neodecanoic acid .sup.(10)Dibutyltin(IV) bisacetylacetonate
Metal(Sn) content: 27.5%
As shown in Table 5, more satisfactory curabilities were displayed
in the cases (Examples 9 to 11) in which the carboxylic acid (B)
was used in combination with a tin carboxylate than in the case
(Comparative Example 8) in which a tin carboxylate was used alone
as the metal carboxylate (D). In particular, when as in Examples 9
and 10, the carboxylic acid (C) was used, a large improvement
effect of the curability was obtained.
Additionally, in the case (Comparative Example 5) in which an
organotin was used, the recovery ratio was poor; on the contrary,
it has been found that the curability can be improved while the
recovery ratio is maintained at a high level, as in Examples 9 to
11, in the case in which the carboxylic acid (B) and a tin
carboxylate as a metal carboxylate were used, where the carbon atom
adjacent to the carbonyl group of each molecule of the carboxylic
acid (B) and/or the metal carboxylate, was a quaternary carbon
atom.
EXAMPLES 12 TO 14 AND COMPARATIVE EXAMPLES 9 AND 10
The reactive silicon group-containing polyoxyalkylene based polymer
(A-4) obtained in Synthesis Example 4 was used as the organic
polymer (A), and a filler, titanium oxide, a plasticizer, an
antisagging agent, an ultraviolet absorber, a photostabilizer, a
dehydrating agent, an adhesion-imparting agent and a crosslinking
agent were weighed out, and a carboxylic acid (B), a metal
carboxylate (D) or an amine compound (E), and an organotin catalyst
were also weighed out to be used as the curing catalysts, according
to the formulations shown in Table 6; all these ingredients were
mixed together with a mixer to prepare one liquid curable
compositions, which were sealed in aluminum cartridges.
By use of the prepared one-component curable compositions, various
physical properties were investigated on the basis of the following
procedures.
(Curing Test)
The curable compositions each were extruded from the cartridge and
filled in a molding frame of about 5 mm in thickness with a
spatula; the surface of each of the filled compositions was fully
flattened, and the planarization completion time was set as the
curing starting time. Every one minute, the surface of each of the
compositions was touched with a spatula, and the skin formation
time was measured as the time when the composition no longer stuck
to the spatula. The skin formation time measurement was made for
each of the compositions, after a storage at 23.degree. C. for 7
days (the initial stage), after a storage at 50.degree. C. for 7
days and after a storage at 50.degree. C. for 4 weeks,
respectively, the elapsed times being counted from the completion
of the one-component cartridge preparation; thus, the curing time
after a varying period of storage was investigated. The results
obtained are shown in Table 6. In the table, A and B denote the
retardation rates of the curing time after storage (the skin
formation time after the storage at 50.degree. C. for 4 weeks/the
initial skin formation time) of less than 1.5 and 1.5 or more,
respectively.
(Tensile Properties of the Cured Substances)
The curable compositions each were filled in a sheet-shaped molding
frame of 3 mm in thickness, the surface of each of the compositions
was fully flattened, and the compositions were aged at 23.degree.
C. for 3 days and additionally at 50.degree. C. for 4 days. The
aged compositions each were blanked into a dumbbell-shaped cured
substance by use of a dumbbell-shaped die. By use of each of these
dumbbell-shaped specimens, the tensile test was carried out at a
tensile rate of 200 mm/min to measure the M50:50% tensile modulus
(MPa), Tb: the tensile strength at break (MPa) and Eb: the
elongation at break (%). The results obtained are shown in Table
6.
(Recovery Ratio)
Reference lines were marked with an interval of 20 mm on the
dumbbell-shaped specimens prepared in a manner similarly to the
above. These specimens were fixed under a condition of 100%
elongation at a constant temperature of 60.degree. C. so that the
reference line interval changed from 20 mm to 40 mm. After 24
hours, the fixation was released and the specimens were allowed to
stand still in a temperature-controlled room at 23.degree. C.; the
recovery ratios after 1 hour were measured. The results obtained
are shown in Table 6.
(Creep Measurement)
Dumbbell-shaped cured substances were prepared in a manner similar
to the above, and one end of each of the dumbbell-shaped specimens
was fixed in an oven at 60.degree. C. to hang each of the
dumbbell-shaped specimens. The lower end of each of the hanging
dumbbell-shaped specimens was subjected to a load of 0.4 times the
M50 value obtained in the above measurement of the tensile
properties of the cured substance concerned. The displacement
difference in the separation between the marked reference lines
between immediately after loading and at an elapsed time of 200
hours was measured. It is to be noted that the smaller is the
displacement difference, the better is the creep resistance. The
results obtained are shown in Table 6.
TABLE-US-00006 TABLE 6 Ex. Comp. ex. 12 13 14 9 10 Organic polymer
(A) A-4 100 100 100 100 100 Filler Hakuenka CCR.sup.(1) Shiraishi
Kogyo Kaisha, Ltd. 120 120 120 120 120 Titanium oxide Tipaque R-820
Ishihara Sangyo Kaisha, Ltd. 20 20 20 20 20 Plasticizer
DIDP.sup.(2) Kyowa Hakko Co., Ltd. 30 30 30 30 Actocol P23.sup.(3)
Takeda Pharmaceutical Co., Ltd. 30 Antisagging agent Disparlon
#6500.sup.(4) Kusumoto Chemicals, Ltd. 2 2 2 2 2 Ultraviolet
Tinuvin 327.sup.(5) Ciba-Geigy Ltd. 1 1 1 1 1 absorber
Photostabilizer Sanol LS-770.sup.(6) Sankyo Co., Ltd. 1 1 1 1 1
Dehydrating agent A-171.sup.(7) Japan Unicar Co., Ltd. 2 2 2 2 2
Adhesion-imparting A-1120.sup.(8) Japan Unicar Co., Ltd. 5 5 5 5 3
agent Crosslinking agent Methyl silicate 51.sup.(9) Colcoat Co.,
Ltd. 2 2 2 2 2 Metal carboxylate Neostann U-50.sup.(10) Nitto Kasei
Co., Ltd. 3.4 3.4 3.4 3.4 (D) Carboxylic acid (C) Versatic
10.sup.(11) Japan Epoxy Resin Co., Ltd. 1 1 1 Amine compound (E)
Laurylamine Wako Pure Chemical Industries, Ltd. 0.75 0.75 0.75
DEAPA.sup.(12) Koei Chemical Industry Co., Ltd. 0.53 Organotin
Neostann U-220.sup.(13) Nitto Kasei Co., Ltd. 2 Curing time Skin
formation time (min) Initial 93 67 78 106 30 After storage at
50.degree. C. for 1 week 91 62 80 170 23 After storage at
50.degree. C. for 4 weeks 110 96 63 210 30 Storage stability Curing
retardation A A A B A Tensile properties 50% Tensile modulus (MPa)
0.83 0.88 0.80 0.75 0.73 Tensile strength at break (MPa) 2.86 2.75
2.44 3.03 2.6 Elongation at break (%) 437 380 385 536 432 Recovery
ratio (%) 70 71 68 72 29 Creep property Displacement difference
(mm) 3 3 3 3 30 .sup.(1)Precipitated calcium carbonate
.sup.(2)Diisodecyl phthalate .sup.(3)PPG3000 .sup.(4)Fatty acid
amide wax
.sup.(5)2-(3,5-Di-t-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole
.sup.(6)Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate
.sup.(7)Trimethoxyvinylsilane
.sup.(8)H.sub.2NC.sub.2H.sub.4NHC.sub.3H.sub.6Si(OMe).sub.3
.sup.(9)Condensate of tetramethoxysilane (Si content: 51%)
.sup.(10)Tin(II) neodecanoate Metal(Sn) content: 22 to 24%
.sup.(11)Neodecanoic acid .sup.(12)3-Diethylaminopropylamine
.sup.(13)Dibutyltin(IV) bisacetylacetonate Metal(Sn) content:
27.5%
As Comparative Example 10 in Table 6 shows, when Neostann U-220, a
tetravalent organotin, was used as the silanol condensation
catalyst, the recovery ratio and the creep resistance were poor. On
the contrary, as Examples 12 to 14 and Comparative Example 9 show,
when Neostann U-50, a divalent tin carboxylate, was used, the
recovery ratio and the creep resistance displayed excellent
results. Moreover, as in Comparative Example 9, only divalent tin
was used but no acid was added, the catalytic activity was found to
be degraded after storage, and hence the curing time was elongated;
however, as in Examples 12 to 14, when an acid was added, the
curing retardation after storage was considerably suppressed. When
DEAPA (3-diethylaminopropylamine) was used as the amine compound
(E), the curability was improved as compared to the case in which
laurylamine was used. Moreover, when PPG3000 was used as a
plasticizer, the curability is somewhat improved as compared to the
case in which DIDP was used, and no curing retardation after
storage was found.
EXAMPLE 15 AND COMPARATIVE EXAMPLE 11
The reactive silicon group-containing polyoxyalkylene based polymer
(A-4) obtained in Synthesis Example 4 was used as the organic
polymer (A), and a filler, a plasticizer, a thixotropy providing
agent, a surface modifier, an ultraviolet absorber and an
antioxidant were weighed out according to the formulations shown in
Table 7; all these ingredients were fully kneaded with a three-roll
paint mill to yield each main component. Then, a dehydrating agent
and an adhesion-imparting agent were weighed out, and a carboxylic
acid (C), a metal carboxylate and an amine compound (E) were also
weighed out to be used as the silanol condensation catalysts, all
these ingredients were added to each main component, and the
mixture thus obtained was mixed under stirring with a spatula for 3
minutes.
(Curing Test)
After mixing, the curable compositions each were filled in a
molding frame of about 5 mm in thickness with a spatula; the
surface of each of the filled compositions was fully flattened, and
the planarization completion time was set as the curing starting
time. Every one minute, the surface of each of the compositions was
touched with a spatula, and the skin formation time was measured as
the time when the composition no longer stuck to the spatula.
(Adhesion Test)
Each of the blended compositions kneaded as described above was
defoamed while being extended thinly with a spatula, put on an
adherend substrate so as to adhere to the adherend substrate, and
the shape of the composition was straightened. After aging at
23.degree. C. for 7 days and additional aging at 50.degree. C. for
3 days, a 90 degree hand peel test was carried out. The breakdown
conditions of the cured substances were observed and the cohesion
failure rates (CF rates) were investigated. In the table, A, B, C,
and D denote the CF rates of 100%, 50% or more, less than 50% and
the 100% interface peeling, respectively. The results obtained are
shown in Table 7.
TABLE-US-00007 TABLE 7 Ex. Comp. ex. Composition (parts by weight)
15 11 Organic polymer (A) A-4 100 100 Filler Hakuenka CCR.sup.(1)
Shiraishi Kogyo Kaisha, 120 120 Ltd. Titanium oxide Tipaque R-820
Ishihara Sangyo Kaisha, 20 20 Ltd. Plasticizer DIDP.sup.(2) Kyowa
Hakko Co., Ltd. 55 55 Antisagging agent Disparlon #6500.sup.(3)
Kusumoto Chemicals, Ltd. 2 2 Ultraviolet absorber Tinuvin
327.sup.(4) Ciba-Geigy Ltd. 1 1 Photostabilizer Sanol
LS-770.sup.(5) Sankyo Co., Ltd. 1 1 Dehydrating agent A-171.sup.(6)
Japan Unicar Co., Ltd. 2 2 Adhesion-imparting agent A-1120.sup.(7)
Japan Unicar Co., Ltd. 3 3 Carboxylic acid (C) Versatic 10.sup.(8)
Japan Epoxy Resin Co., 0.2 0.2 Ltd. Metal carboxylate Neostann
U-50.sup.(9) Nitto Kasei Co., Ltd. 3.2 Bismuth(III) Aldrich Ltd. 5
neodecanoate Amine compound (E) DEAPA.sup.(10) Wako Pure Chemical
0.5 0.5 Industries, Ltd. Curing time Skin formation time (min) 34
60 Adhesion 90 Degree hand peel Glass A A Anode oxidized aluminum A
D Stainless steel plate A D .sup.(1)Precipitated calcium carbonate
.sup.(2)Diisodecyl phthalate .sup.(3)Fatty acid amide wax
.sup.(4)2-(3,5-Di-t-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole
.sup.(5)Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate
.sup.(6)Trimethoxyvinylsilane
.sup.(7)H.sub.2NC.sub.2H.sub.4NHC.sub.3H.sub.6Si(OMe).sub.3
.sup.(8)Neodecanoic acid .sup.(9)Tin(II) neodecanoate Metal(Sn)
content: 22 to 24% .sup.(10)3-Diethylaminopropylamine
As shown in Table 7, when a metal carboxylate and a carboxylic acid
in each of which the carbon atom adjacent to the carbonyl group is
a quaternary carbon atom, were used, excellent curability was
displayed. Additionally, when tin neodecanoate was used, curable
compositions also excellent in adhesion were obtained.
INDUSTRIAL APPLICABILITY
According to the present invention, a curable composition
comprising a reactive silicon group-containing organic polymer (A)
and a carboxylic acid (B),
(I) wherein the composition comprises, as the carboxylic acid (B),
a carboxylic acid (C) in which the carbon atom adjacent to the
carbonyl group is a quaternary carbon atom, and/or
(II) wherein the composition comprises a metal carboxylate (D)
formed between the carboxylic acid in which the carbon atom
adjacent to the carbonyl group is a quaternary carbon atom and a
metal atom of 208 or less in atomic weight, and the curable
composition has a high recovery ratio and a high creep resistance,
and little displays degradation of the catalytic activity after
storage, and provides a practical curability.
* * * * *